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. | Joss, Addie | (sheus37393) | Cancun Chaos | 30 |
| 2. | McLain, Denny | (Swingindave) | ARKANSAS DELTA KICKERS | 30 |
| 3. | Koufax, Sandy | (Swingindave) | ARKANSAS DELTA KICKERS | 29 |
| 4. | Tesreau, Jeff | (walle-1) | Dallas Mustangs | 29 |
| 5. | Hamels, Cole | (filler8) | Boulder Cavemen | 29 |
| 6. | McGinnity, Joe | Toronto Tigers | 29 | |
| 7. | Drysdale, Don | (sheikyerboudi) | Mojave Desert Route 666ers | 29 |
| 8. | Sabathia, CC | (dynasty8) | New Jersey Devils | 29 |
| 9. | Andujar, Joaquin | (walle-2) | Iowa Pigs | 29 |
| 10. | Plesac, Zach | (dynasty) | Kentucky Horses | 29 |
| 11. | Sutton, Don | (walle-1) | San Diego Sharks | 29 |
| 12. | Lyons, Ted | Milwaukee Skeletons | 28 | |
| 13. | Cicotte, Eddie | (walle-2) | Utah Nightmares | 28 |
| 14. | Sutton, Don | (walle-2) | Chicago Reapers | 28 |
| 15. | Bender, Chief | (richp) | Beantown Bombers | 28 |
| 16. | Ford, Whitey | (todorojo) | Spanish Fork Toros | 28 |
| 17. | Shields, James | (dynasty8) | Alaska Red Bears | 28 |
| 18. | Swindell, Greg | (dynasty8) | Kentucky Horses | 28 |
| 19. | Vander Meer, Johnny | (finalbody) | Atlanta Gorillas | 28 |
| 20. | Taylor, Jack | (WorcWarr) | Worcester Warriors | 28 |
| 21. | Pfiester, Jack | (hayzess) | Brooklyn Bridegrooms | 28 |
| 22. | Blyleven, Bert | (Rainman) | Salem Demons | 28 |
| 23. | Reulbach, Ed | (sheikyerboudi) | Schlitz Brewmeisters | 28 |
| 24. | Sweeney, Charlie | (dynasty) | Texas Outlaws | 28 |
| 25. | Chance, Dean | (CoachHollett) | Boston Bees | 28 |
| 26. | Krukow, Mike | (dynasty) | Boulder Cavemen | 28 |
| 27. | Wood, Joe | (walle-2) | Carolina Bulldogs | 28 |
| 28. | Joss, Addie | (kungfu77) | Minnesota Hi-Ballers | 28 |
| 29. | White, Doc | Salem Demons | 28 | |
| 30. | McGinnity, Joe | (dynasty) | Pittsburgh Plunder | 28 |
| 31. | Viola, Frank | (walle-1) | New Jersey Devils | 28 |
| 32. | White, Doc | (rlapierre) | DEATH VALLEY REAPERS | 28 |
| 33. | Cicotte, Eddie | (filler8) | Kansas Grasshoppers | 28 |
| 34. | Saberhagen, Bret | (Esmith) | Chicago Reapers | 28 |
| 35. | Newcombe, Don | (dynasty) | Seattle Sloths | 28 |
| 36. | Tanana, Frank | Sacramento Lions | 28 | |
| 37. | Drysdale, Don | (filler8) | Miami Serpents | 28 |
| 38. | Chesbro, Jack | (sheikyerboudi) | Dog Breath in the YearOfThePlague | 28 |
| 39. | Halladay, Roy | (godelfan) | Beaverdale Borg | 28 |
| 40. | Hendrix, Claude | (sheikyerboudi) | Burnt Weeny Sandwich | 28 |
| 41. | Pfiester, Jack | (sheikyerboudi) | Burnt Weeny Sandwich | 28 |
| 42. | McLain, Denny | (athlete4) | NASHVILLE NIGHT RIDERS | 28 |
| 43. | Krukow, Mike | (dynasty) | Pittsburgh Plunder | 27 |
| 44. | Marichal, Juan | (dynasty) | Carolina Bulldogs | 27 |
| 45. | Cicotte, Eddie | Nevada Snakes | 27 | |
| 46. | Wegman, Bill | (dynasty8) | Texas Outlaws | 27 |
| 47. | Hamels, Cole | Arizona Suns | 27 | |
| 48. | Weaver, Jered | Chicago Reapers | 27 | |
| 49. | Young, Cy | (walle-2) | Charlotte Spiders | 27 |
| 50. | Pfiester, Jack | Sacramento Lions | 27 |
