Favorite Teams leagues are not included in Single-Season records. Records only remain for 10 seasons.
Single-Season Leaders (Losses)
Average
OBP
SLG
OPS
At Bats
Runs
Hits
Doubles
Triples
Homers
RBIs
Walks
Strikeouts
Stolen Bases
Caught Stealing
Sac Hits
Sac Fly
HBP
GIDP
D+/-
Wins
Losses
ERA
WHIP
Innings
Hits Allowed
HR Allowed
Walks (P)
Strikeouts (p)
Complete Games
Saves
Blown Saves
Shutouts
Quality Starts
Wild Pitches
Hit Batters
H/9
BB/9
SO/9
| 1. | McLain, Denny | (dynasty) | Pittsburgh Plunder | 30 |
| 2. | Joss, Addie | (filler8) | Kentucky Horses | 30 |
| 3. | Sabathia, CC | (dom1134157) | Florida Gators | 29 |
| 4. | Hamels, Cole | (walle-1) | Louisiana Gators | 29 |
| 5. | Tesreau, Jeff | (filler8) | Seattle Sloths | 29 |
| 6. | Koufax, Sandy | (dynasty) | Pittsburgh Plunder | 29 |
| 7. | McGinnity, Joe | (Ask12be1) | Bronx Hitmen | 29 |
| 8. | Drysdale, Don | (dynasty) | Arizona Suns | 29 |
| 9. | Plesac, Zach | (hanson) | Oconee Riverdawgs | 29 |
| 10. | Sutton, Don | Arizona Suns | 29 | |
| 11. | Andujar, Joaquin | (dynasty8) | Utah Nightmares | 29 |
| 12. | Ford, Whitey | (filler8) | Nevada Snakes | 28 |
| 13. | Shields, James | (dynasty) | Arizona Suns | 28 |
| 14. | Swindell, Greg | (jeffky1229) | Louisville Union | 28 |
| 15. | Taylor, Jack | (WorcWarr) | Worcester Warriors | 28 |
| 16. | Halladay, Roy | (rlapierre) | MAINE BLACK BEARS | 28 |
| 17. | Wood, Joe | (Ask12be1) | Tucson Dirt Devils | 28 |
| 18. | Bender, Chief | Charlotte Spiders | 28 | |
| 19. | Chesbro, Jack | (sheikyerboudi) | 12th Man Expendables 5 | 28 |
| 20. | McLain, Denny | (jaredhamann) | NASHVILLE NIGHT RIDERS | 28 |
| 21. | Drysdale, Don | (dynasty8) | Utah Nightmares | 28 |
| 22. | White, Doc | (dynasty8) | Pittsburgh Plunder | 28 |
| 23. | Cicotte, Eddie | (dynasty) | Utah Nightmares | 28 |
| 24. | Chance, Dean | (walle-1) | Boston Bees | 28 |
| 25. | Joss, Addie | (JohnHeidy) | Highland Hi-Ballers | 28 |
| 26. | Sweeney, Charlie | Utah Nightmares | 28 | |
| 27. | Tanana, Frank | (sthompson77566) | Texas Tigers | 28 |
| 28. | Newcombe, Don | (vonveezil) | Florida Crabs | 28 |
| 29. | Lyons, Ted | (dynasty8) | Texas Outlaws | 28 |
| 30. | Reulbach, Ed | (walle-2) | Pittsburgh Plunder | 28 |
| 31. | Pfiester, Jack | (filler8) | Portland Vikings | 28 |
| 32. | Blyleven, Bert | (TheVinci) | Kentucky Horses | 28 |
| 33. | Sutton, Don | Seattle Dirt Devils | 28 | |
| 34. | Krukow, Mike | (filler8) | Montana Ducks | 28 |
| 35. | Vander Meer, Johnny | (dynasty8) | Sacramento Lions | 28 |
| 36. | White, Doc | (walle-1) | Atlanta Gorillas | 28 |
| 37. | McGinnity, Joe | (dynasty) | Kentucky Horses | 28 |
| 38. | Viola, Frank | (dynasty) | Texas Outlaws | 28 |
| 39. | Cicotte, Eddie | (Klose_Call) | Burnham Big Blues | 28 |
| 40. | Hendrix, Claude | (dynasty) | Sacramento Lions | 28 |
| 41. | Pfiester, Jack | (dynasty) | Sacramento Lions | 28 |
| 42. | Saberhagen, Bret | (Klose_Call) | Greenwich Nationals | 28 |
| 43. | Pfiester, Jack | (dcwabdi) | Red Wing Rhino's | 27 |
| 44. | Caldwell, Ray | (kgonzales2014) | Dallas Mustangs | 27 |
| 45. | Young, Cy | (jas202) | Pete Rose Gamblers | 27 |
| 46. | Pfiester, Jack | (Ask12be1) | Dallas Dirt Devils | 27 |
| 47. | Ford, Russ | (filler8) | Kentucky Horses | 27 |
| 48. | Cicotte, Eddie | (JohnHeidy) | Hamburg Chili Dodgers | 27 |
| 49. | Valdez, Ismael | (dynasty) | Minnesota Frogs | 27 |
| 50. | Burkett, John | Boulder Cavemen | 27 |
