Single Season Pitching Records - Modern Era (1958-Present)
Regular season statistics only, updated through the conclusion of the 2024 season.
* Denotes record set in a 42-game season.
N.B. Intercounty Records are divided into two eras, in the Post War Era (1946-1957) teams played up to a 60-game schedule, while in the Modern Era (1958-Present) the longest schedule has traditionally been only 36 games.
From 2013 to 2022 to today, teams have played 42-game seasons. Also, no official statistics are available from the post-WWII era, while the Modern Era is complete.
| Most Appearances | Bob Johnstone | 1970 | Toronto | 26 | |
| Most Wins | Wallace "Spud" Bush | 1961 | Brantford | 16 | |
| Most Loses | Greg Kingdon | 1965 | Listowel | 11 | |
| Most Saves | * | Deivy Mendez | 2024 | Welland | 12 |
| Kyle Payne | 2008 | Barrie | 11 | ||
| * | Deivy Mendez | 2023 | Welland | 10 | |
| Enerio Del Rosario | 2017 | Barrie | 9 | ||
| Miguel Lahera | 2018 | Kitchener | 8 | ||
| Most Complete Games | Wallace "Spud" Bush | 1961 | Brantford | 15 | |
| Best Won-Lost Percentage | * | Claudio Custodio (11-0) | 2022 | Guelph | 1.000 |
| Marshall Gates (11-0) | 1973 | Toronto | 1.000 | ||
| * | Owen Boon (10-0) | 2022 | London | 1.000 | |
| Jeff Jens (10-0) | 1978 | Stratford | 1.000 | ||
| Emilis Guerrero (9-0) | 2017 | Barrie | 1.000 | ||
| Mark Fraser (9-0) | 1995 | Stratford | 1.000 | ||
| Craig Kennedy (9-0) | 1976 | Brantford | 1.000 | ||
| Mike Kilkenny (9-0) | 1975 | London | 1.000 | ||
| Lowest Earned Run Average (45 IP Min.) | Bob Bodden | 1975 | Brantford | 0.29 | |
| Frank Garces | 2018 | Barrie | 0.38 | ||
| Stefan Strecker | 2009 | Brantford | 0.79 | ||
| Scott Medvin | 1998 | Kitchener | 0.86 | ||
| Brian Murphy | 1968 | London | 0.93 | ||
| Most Innings Pitched | Ron Stead | 1960 | Brantford | 149 | |
| * | Claudio Custodio | 2022 | Guelph | 120 | |
| Most Batters Faced | Bob Lory | 1978 | St. Thomas | 622 | |
| Most Hits Allowed | J.P. Groulx | 1985 | Brantford | 151 | |
| Bob Lory | 1978 | St.Thomas | 151 | ||
| Most Runs Allowed | Harry Costello | 1988 | Hamilton | 101 | |
| Most Earned Runs Allowed | Harry Costello | 1988 | Hamilton | 78 | |
| Mark Jeans | 1986 | Hamilton | 78 | ||
| Most Home Runs Allowed | Keith Johns | 1993 | St. Thomas | 19 | |
| Most Bases On Balls Issued | Mark Jeans | 1987 | Hamilton | 87 | |
| Most Strikeouts | * | Claudio Custodio | 2022 | Guelph | 196 |
| Ron Stead | 1965 | Brantford | 155 | ||
| Rob Blumberg | 1988 | Stratford | 133 | ||
| * | Jose Arias | 2022 | London | 132 | |
| Bob Johnstone | 1970 | Toronto | 130 | ||
| Most Hit Batters | Cory Hammond | 2008 | Stratford | 16 | |
| Roy McKay | 1958 | London | 16 | ||
| Most Wild Pitches | Dwight Griese | 1982 | Guelph | 32 |