Short Answer

Both the model and the market expect 4+ Home runs in a pro baseball game in 2026, with no compelling evidence of mispricing.

1. Market Behavior & Drivers

The market has traded between 24.0% and 25.0% YES probability, with a current reading of 25.0%. Total volume: 50 contracts.
  • Four elite power hitters possess high multi-homer game capability.
  • The 2026 Home Run per Fly Ball rate indicates a notable decline.
  • Arizona Diamondbacks and Washington Nationals bullpens exhibit significant weaknesses.
  • Historically, one-third of 4-homer games occurred after the All-Star break.
  • No player has achieved four home runs yet despite recent high offense.

Who Wins and Why

Outcome Market Model Why
4+ Home runs 25.0% 25.0% The evidence confirms the extreme rarity of a player hitting 4+ home runs in a single MLB game, with only 21 occurrences of exactly 4 HRs and none for 5+, which supports the market's relatively low debiased price of 25%, while the record 3 games in 2025 is balanced by no occurrences yet in 2026.

Current Context

Prediction markets indicate a modest chance for a 4-homer game in 2026. As of late April 2026, the 'Yes' odds for an MLB player hitting four or more home runs in a single game during the 2026 season are between 24-34% [1][2]. The 2026 MLB regular season runs until approximately September 28, with market resolution based on official post-season MLB statistics [2]. Currently, no single-player four-homer games have been recorded in 2026 [3]. The most recent instance of a player achieving this feat was on August 28, 2025, by Kyle Schwarber [4].
Several players have displayed significant home run power early this season. Cleveland Guardians rookie Chase DeLauter hit four home runs across his first three career games in late March 2026, joining Trevor Story (2016) as the only players to achieve this in their first three regular season appearances [5]
-Trevor Story, 2016 -Chase DeLauter, 2026" aria-label="Source 6: Players to hit 4 home runs in first 3 career regular season games:</p><p>-Trevor Story, 2016 -Chase DeLauter, 2026" data-citation-label="Players to hit 4 home runs in first 3 career regular season games:</p><p>-Trevor Story, 2016 -Chase DeLauter, 2026">[6]. Additionally, Nathan Church recorded two home runs in a single game on April 25, 2026, against the Mariners, marking his fourth home run of the season [7].
Sources (7)
  1. 1MLB: 4-homer game in 2026?polymarket.com
  2. 2MLB: 4-homer game in 2026? Predictions & Odds | Polymarketpolymarket.com
  3. 3Players To Hit 4 Home Runs In One MLB Game | StatMusestatmuse.com
  4. 4Most Recent 4 Home Run Game | StatMusestatmuse.com
  5. 5Chase DeLauter homers four times in first three games | 03/28/2026 | MLB.commlb.com
  6. 6Players to hit 4 home runs in first 3 career regular season games:</p><p>-Trevor Story, 2016 -Chase DeLauter, 2026threads.com
  7. 7Mariners outlast Cardinals 11-9 in game that featured 8 home runs | FOX Sportsfoxsports.com

2. Price Chart

Historical Price (Probability)

Outcome probability
Date

3. Market Data

Contract Snapshot

This market resolves to "Yes" if any hitter records 4 or more home runs in any game during the 2026 Pro Baseball regular season or playoffs; otherwise, it resolves to "No." The market closes either after this event occurs or by December 3, 2026, at 10:00 AM EST, with resolution based on sources like ESPN, MLB.com, and Fox Sports. Insider trading by current/former league personnel, team owners, and their immediate families is prohibited.

Available Contracts

Market options and current pricing

Outcome bucket Yes (price) No (price) Last trade probability
4+ Home runs $0.25 $0.83 25%

Market Discussion

As of late April 2026, no MLB player has hit four or more home runs in a single game this season, despite some recent games featuring a high total number of home runs distributed among players [1]. Historically, there have been 21 instances of a single player hitting 4+ HRs in a game since 1894, with three occurring in the 2025 season alone [2]. The market currently estimates a 24-34% chance of at least one such game in the 2026 regular season [3], supported by power hitters like Aaron Judge, Kyle Schwarber, and Yordan Alvarez showing strong early-season performance [4].

Sources (4)
  1. 1Mariners outlast Cardinals 11-9 in game that featured 8 home runs | FOX Sportsfoxsports.com
  2. 2Four home run games in MLB historymlb.com
  3. 3MLB: 4-homer game in 2026? Predictions & Odds | Polymarketpolymarket.com
  4. 4Yordan Alvarez HR, Otto Lopez Hits, Kyle Schwarber Total Bases — MLB Batter Props April 20, 2026bettorsinsider.com

4. Trust Index

Octagon Trust Index Kalshi 75 Good

Primary risk· Trade quality

How it adds up
Integrity80% of score84Good
Trade quality20% of score38High Risk
Trust score75Good

Weighted blend with hard caps — a critically weak safety pillar, or a severe trading anomaly, caps the total regardless of the rest. Full methodology · About the Trust Index

Trust profile
Integrity4 screens run · 6 don't apply
Market integrity
83Good

Outcome is hard to influence

No suspicious activity on any screen

Screened clean
Large tradesNo single trade dominates the tape. Clear
Thin-volume movesNo significant move Clear
Size patternsNo distribution read Clear
2 screens not run
Outcome control · doesn't apply to this market type
Thin-leg conviction · doesn't apply to this market type
Info fairness
80Good

Structural prior — no screens apply

No suspicious activity on any screen

Screened clean
Information exposureNo concentrated group can know the outcome materially early. Clear
4 screens not run
Move vs. catalyst · doesn't apply to this market type
Longshot repricing · doesn't apply to this market type
Pre-broadcast certainty · doesn't apply to this market type
Cross-venue timing · doesn't apply to this market type
Resolution quality
92Strong

Resolution mechanism is dependable

No suspicious activity on any screen

Resolution rules read: Clear

Liquidity
38Very thin

Hard to fill near the screen price

1 contract

4+ Home runs38
Very thin · low confidence

Light recent trading — size may not fill near the screen price.

Move quality
70Stable

No significant moves

1 contract

4+ Home runs—
No significant move (6h)

Price was stable over the last 6 hours.

Rule clarity
95Clear

Counts toward Resolution quality, not here

1 contract

4+ Home runs95
Clear · high confidence

Objective result from a trusted source (allowlist)

allowlist · Clear
Trade quality
38High Risk

Thin market — entering or exiting at fair value will be difficult.

Outcome quality 38 (notional-weighted)

4+ Home runs38Market scoreLiquidity38Move quality–Rule clarity95
Why 38
Liquidity
38 · Very thin · low confidence

Light recent trading — size may not fill near the screen price.

Move quality
No significant move (6h)

Price was stable over the last 6 hours.

Rule clarity
95 · Clear · high confidence

Objective result from a trusted source (allowlist)

allowlist · Clear

underwriting_v1.4 · computed Oct 1, 2026

5. Are Top Power Hitters Scheduled Against Weak HR/9 Pitching?

Aaron Judge 2026 ISO.370 (top 1%) [1][2]
Yordan Alvarez Barrel%20.1% (98th percentile) [1][2][3][4]
Mike Trout Barrel%25.8% (99th percentile) [1][2][3][5][6]
Four active players demonstrate elite power-hitting capabilities based on key metrics. Aaron Judge, Yordan Alvarez, Mike Trout, and Matt Olson are identified as top power hitters, consistently ranking in the top 10% of the league for both Barrel Rate and Isolated Power (ISO). Each player also has at least three career games with two or more home runs. Aaron Judge's 2026 Isolated Power is.370, placing him in the top 1% [1][2], with a Barrel% ranging from approximately 15-24% [1][2][3][7][8]. Yordan Alvarez boasts an elite 2026 ISO of.381 and a 20.1% Barrel Rate, ranking in the 98th percentile [1][2][3][4]. Mike Trout's 2026 ISO is.321 (top 10%) with a 25.8% Barrel Rate (99th percentile) [1][2][3][5][6]. Matt Olson's 2026 ISO is.320 (top 10%) complemented by a top-tier Barrel Rate [1][9][3].
Specific schedule information against weak pitching staffs remains largely undefined. Despite these impressive individual power-hitting metrics, the research provides limited definitive information regarding their upcoming schedules against pitching staffs specifically within the bottom quintile for home runs allowed per nine innings (HR/9). While a New York Yankees schedule versus bottom HR/9 is noted as possible for Aaron Judge [7][8], Yordan Alvarez is mentioned as facing HR-prone staffs, which does not align with the defined weak pitching criterion [1][2][3][4]. Similarly, descriptions of Mike Trout's "upcoming vs poor pitching" [1][2][3][5][6] and Matt Olson's Atlanta schedule having "opportunities" [1][9][3] do not explicitly confirm that their opponents are in the bottom quintile for HR/9. Consequently, the available research does not fully specify their upcoming schedule matchups against pitching staffs meeting the precise definition of being in the bottom quintile for home runs allowed per nine innings for all mentioned players, indicating a gap in the current data regarding specific favorable pitching matchups for all four sluggers [1][2][3][7][8][4][5][6][9].
Sources (9)
  1. 1Major League Leaderboards - 2026 - Batting | FanGraphs Baseballfangraphs.com
  2. 2Major League Leaderboards - 2026 - Batting | FanGraphs Baseballfangraphs.com
  3. 3Most Games With 2 Home Runs Active Player | StatMusestatmuse.com
  4. 4Yordan Alvarez (OF) - HOU MLB Stats & Averages 2026 | FTAfantasyteamadvice.com
  5. 5Mike Trout - Stats - Batting | FanGraphs Baseballfangraphs.com
  6. 6Mike Trout is Hitting Well Even if His Batting Average Doesn't Say Itsi.com
  7. 7Aaron Judge - Stats - Batting | FanGraphs Baseballfangraphs.com
  8. 8Aaron Judge (OF) - NYY MLB Stats & Averages 2026 | FTAfantasyteamadvice.com
  9. 9Major League Leaderboards - 2026 - Batting | FanGraphs Baseballfangraphs.com

6. What Are Hitter-Friendly MLB Park Schedules for Summer?

Coors Field Park Factor112 overall, 125 runs (2024-2026) [1]
Great American Ball Park HR Factor122 [1][2]
Guaranteed Rate Field HR Factor106 [1]
Specific game schedules and pitcher data remain largely unavailable. While complete schedules for June, July, and August 2026 at Coors Field, Great American Ball Park, and Guaranteed Rate Field are not yet fully specified, projections indicate a substantial number of home games. Coors Field is expected to host over 40 home games during this period [3], Guaranteed Rate Field approximately 35 [4], and Great American Ball Park around 25 [5]. However, specific dates, matchups, and detailed pitcher statistics, such as a starting pitcher's flyball rate exceeding 45%, are currently not accessible.
Coors Field and Great American Ball Park are notably hitter-friendly venues. These ballparks are renowned for characteristics that favor hitters, particularly Coors Field, which recorded an overall park factor of 112 and a run factor of 125 for the 2024-2026 period [1]. Great American Ball Park also presents a significant advantage for offense, featuring a home run factor of 122 and a run factor of 106 [1][2].
Guaranteed Rate Field also offers favorable hitting conditions for home runs. Despite having an overall run factor between 96 and 98, Guaranteed Rate Field is still recognized as a hitter-friendly stadium, distinguished by a home run factor of 106 [1]. These collectively favorable hitting conditions across all three parks contribute to the high probability observed in the 'Pro Baseball: 4+ Home Run Game' prediction market [1][2].
Sources (5)
  1. 1Statcast Park Factors | baseballsavant.combaseballsavant.mlb.com
  2. 2MLB Park Factors 2026 – Stadium Betting Impactbestmlbhandicapper.com
  3. 32026 Colorado Rockies Schedule | Baseball-Reference.combaseball-reference.com
  4. 4Chicago White Sox 2026 Home Games Schedule: Complete Guidebattingcagesnearby.com
  5. 52026 Cincinnati Reds Schedule | July to September | FantasyProsfantasypros.com

7. How Does the 2026 HR/FB Rate Compare to Recent Seasons?

2026 HR/FB Rate8.4% [1]
2019 HR/FB Rate10.9% [2]
2026 Home Runs Below Expected17% [3]
The 2026 Home Run per Fly Ball rate indicates a notable decline. The league-wide Home Run per Fly Ball (HR/FB) rate for the 2026 season currently stands at 8.4% [1]. This marks a decrease when compared to recent seasons, particularly the 2019 season, which was recognized for a livelier ball, when the rate was 10.9% [2]. The 2026 rate is also lower than the 8.8% observed in 2024 [4] and the 9.1% recorded in 2025 [5], and it is slightly below the approximate 8.5% from 2023 [6].
Several factors appear to explain the current season's lower home run output. For the early part of the 2026 season, home runs are 17% below expected outcomes, with 13% fewer fly balls identified as home run candidates compared to the 2025 season [3]. Observations suggest that pitchers in 2026 are throwing a higher percentage of non-competitive pitches, at 16% versus 12% previously, which results in a lower home run chance per pitch of 0.67% compared to 0.77% [3]. However, the available research does not provide information on whether this trend is accelerating or decelerating as the season progresses into the summer months.
Sources (6)
  1. 12026 Major League Baseball Batting Ratios | Baseball-Reference.combaseball-reference.com
  2. 22019 Major League Baseball Batting Ratios | Baseball-Reference.comaws.baseball-reference.com
  3. 3The State of Home Runs So Far in 2026 | Ballpark Palballparkpal.com
  4. 42024 Major League Baseball Batting Ratios | Baseball-Reference.combaseball-reference.com
  5. 52025 Major League Baseball Batting Ratios | Baseball-Reference.combaseball-reference.com
  6. 62023 Major League Baseball Batting Ratios | Baseball-Reference.combaseball-reference.com

8. Which MLB Teams Have the Worst Bullpen ERA and Inherited Runners Scored?

Arizona Diamondbacks Bullpen ERA6.50 [1]
Washington Nationals Bullpen ERA6.34 [1]
Washington Nationals Inherited Runners Scored Percentage49% [2]
The Arizona Diamondbacks and Washington Nationals exhibit significant bullpen weaknesses. Both teams are currently among the bottom five in Major League Baseball for overall bullpen ERA and inherited runners scored percentage. The Diamondbacks report a bullpen ERA of 6.50 [1] and an inherited runners scored percentage of 31% [2]. Similarly, the Nationals have a bullpen ERA of 6.34 [1] and a significantly higher inherited runners scored percentage of 49% [2].
These teams rank among the weakest bullpens in both crucial statistics. Beyond these two clubs, other teams with notably poor bullpen ERAs include Tampa Bay (7.34), Houston (6.60), and St. Louis (6.15) [1]. In terms of inherited runners scored percentage, other high-ranking teams include the Los Angeles Angels (42%), Milwaukee (43%), New York Mets (40%), and Oakland (29%) [2][1]. These statistics firmly place the Diamondbacks and Nationals among the weakest bullpens in both key metrics.
Quantified remaining game schedules against top-slugging teams are unavailable. While the Diamondbacks and Nationals show critical bullpen weaknesses, the available research does not quantify their remaining games specifically against top-slugging percentage teams such as the Dodgers, Astros, Braves, Nationals (who are also a top-slugging team), and Marlins [3][4]. Teams have played approximately 28-30 games, with about 130 games remaining in the season [4].
Sources (4)
  1. 1MLB Team Bullpen Stats 2026 - ERA, WHIP, Saves & Morecovers.com
  2. 22026 Major League Baseball Relief Pitching | Baseball-Reference.combaseball-reference.com
  3. 3MLB Stats - MLB Team Slugging % | TeamRankings.comteamrankings.com
  4. 42026 Athletics Schedule | Baseball-Reference.combaseball-reference.com

9. How Many 4-Homer Games Occurred Post-All-Star Break?

4-Homer Games Post-All-Star Break (as of Aug 2025)7 of 21 total games [1][2][3][4]
Percentage of 4-Homer Games Post-All-Star Break33% [1][2][3][4]
2026 All-Star Game DateJuly 14 [5][6][7]
A significant portion of 4-homer games occurred post-All-Star break historically. As of August 2025, 33% of all recorded 4-homer games in Major League Baseball (MLB) history have taken place after the All-Star break [1][2][3][4]. This accounts for 7 of the 21 total instances of a player hitting four home runs in a single game. However, the research noted that statistics specifically for the 18 all-time 4-homer games, as referenced in the query, were not provided, with the available data based on 21 total games.
The 2026 season's All-Star break precedes prominent power hitters' schedules. The 2026 MLB All-Star Game is scheduled for July 14, with the regular season concluding on September 27 [5][6][7]. Several prominent power hitters identified for the 2026 season include Ohtani, Judge, Raleigh, Schwarber, Suarez, and Kurtz [8][9][10]. However, the available research does not provide information regarding whether these identified players will face advantageous schedules, such as prolonged stretches against struggling teams or games in favorable ballparks, during the post-All-Star break segment of the 2026 season.
Sources (10)
  1. 1List of Major League Baseball single-game home run leaders - Wikipediawikipedia.com
  2. 2List of 4-home-run games in Major League Baseballwidescreenings.com
  3. 3Four home run games in MLB historymlb.com
  4. 4MLB Players Who Hit 4 Home Runs in 1 Game | Baseball Almanacbaseball-almanac.com
  5. 5MLB All-Star Week 2026 Schedule | MLB.commlb.com
  6. 62026 Major League Baseball season - Wikipediaen.wikipedia.org
  7. 7Press release: MLB announces 2026 regular season schedulemlb.com
  8. 8MLB history: Five sluggers with 30+ HR at the All-Star break - Yahoo Sportssports.yahoo.com
  9. 9Today’s top 10 most likely home run hitters, plus +680 pick for Sunday [4/26/2026]dimers.com
  10. 10Who Will Hit the Most Home Runs in the 2026 MLB Season? 5 Predictionsprizepicks.com

10. What Could Change the Odds

Key Catalysts

The market probability for a player to hit four or more home runs in a 2026 MLB regular season game currently ranges from 24-34% on Polymarket as of late April 2026 [1]. This includes inside-the-park home runs according to official MLB rules [1]. Despite recent high-offense days, including one on April 14 where nine players hit multiple home runs, no player has yet achieved four or more home runs in a single game in the 2026 season [2][3].
Historically, there have been 21 instances of a player hitting four or more home runs in an MLB game [4]. A significant recent acceleration saw three such games occur in the 2025 season, with Suarez in April, Kurtz in July, and Schwarber in August [4]. This recent precedent suggests that while still a rare occurrence, it is not an anomaly and has demonstrated a higher frequency in the immediate past.
A major catalyst for a "Yes" outcome would be an outstanding performance from a premier power hitter. Players like Ben Rice, Brandon Lowe, and Aaron Judge are currently among the favorites in betting markets to lead the league in home runs [5][6]. Aaron Judge, for instance, is strongly favored at approximately 49% odds to hit 50 or more home runs this season, indicating a high potential for individual players to have exceptionally productive games, which could include a rare four-homer outing [7].

Key Dates & Catalysts

  • Expiration: December 03, 2026
  • Closes: December 03, 2026
Sources (7)
  1. 1MLB: 4-homer game in 2026? Predictions & Odds | Polymarketpolymarket.com
  2. 2Monday’s epic home run barrage nearly makes MLB history - Yahoo Sportssports.yahoo.com
  3. 3Aaron Judge, Mike Trout among nine players with multi-homer games Monday - CBS Sportscbssports.com
  4. 4List of Major League Baseball single-game home run leadersen.wikipedia.org
  5. 5MLB: Home Runs Leader Predictions & Odds 2026 | Polymarketpolymarket.com
  6. 6Predicting the MLB Home Run Leader: Aaron Judge vs. Kyle Schwarber vs. Shohei Ohtanisi.com
  7. 7Will Anyone Hit 50 Home Runs This Season?actionnetwork.com