qSeason Leaders by league, Losses
| Seg |
Lg |
SName |
Player |
Tm |
G |
W |
L |
IP |
| Lg | CFL | 2005 | BENSON,Kris | NAP | 27 | 5 | 20 | 181.1 |
| Lg | CFL | 2005 | JOHNSON,Jason | SP6 | 33 | 7 | 20 | 206.0 |
| Lg | CFL | 2005 | RADKE,Brad | SYR | 33 | 6 | 20 | 207.1 |
| Lg | CFL | 2006 | MOYER,Jamie | MMW | 35 | 6 | 22 | 218.1 |
| Lg | CFL | 2007 | GLAVINE,Tom | DFW | 34 | 6 | 22 | 204.1 |
| Lg | CFL | 2008 | ARROYO,Bronson | ABB | 33 | 9 | 19 | 205.2 |
| Lg | CFL | 2008 | LANNAN,John | AFS | 38 | 6 | 19 | 196.2 |
| Lg | CFL | 2009 | PELFREY,Mike | OMR | 35 | 7 | 23 | 184.1 |
| Lg | CFL | 2010 | GARLAND,Jon | SEA | 37 | 3 | 21 | 206.2 |
| Lg | CFL | 2010 | RODRIGUEZ,Wandy | JBE | 38 | 8 | 21 | 212.2 |
| Lg | CFL | 2010 | WOLF,Randy | MMW | 34 | 6 | 21 | 233.0 |
| Lg | CFL | 2011 | LILLY,Ted | WAS | 34 | 12 | 16 | 197.0 |
| Lg | CFL | 2011 | SANCHEZ,Anibal | SEA | 34 | 6 | 16 | 206.0 |
| Lg | CFL | 2012 | VARGAS,Jason | CRS | 33 | 13 | 17 | 223.2 |
| Lg | CFL | 2012 | NORRIS,Bud | OMR | 31 | 6 | 17 | 176.1 |
| Lg | CFL | 2012 | CAHILL,Trevor | BB | 32 | 7 | 17 | 188.1 |
| Lg | CFL | 2013 | LACKEY,John | MMW | 32 | 7 | 16 | 206.2 |
| Lg | CFL | 2013 | CORREIA,Kevin | CRS | 31 | 9 | 16 | 176.0 |
| Lg | CFL | 2013 | BAILEY,Homer | BB | 32 | 11 | 16 | 218.2 |
| Lg | CFL | 2014 | SANTANA,Ervin | BB | 33 | 4 | 22 | 192.0 |
| Lg | CFL | 2015 | SIMON,Alfredo | CRS | 38 | 7 | 20 | 185.1 |
| Lg | CFL | 2016 | STEPHENSON,Robert | CRS | 33 | 4 | 23 | 149.1 |
| Lg | CFL | 2017 | TAILLON,Jameson | HTA | 27 | 5 | 19 | 141.1 |
| Lg | CFL | 2018 | SANCHEZ,Aaron | OMR | 31 | 0 | 17 | 118.2 |
| Lg | CFL | 2019 | LAUER,Eric | TZD | 28 | 6 | 16 | 152.1 |
| Lg | CFL | 2020 | HOWARD,Spencer | HVL | 28 | 4 | 17 | 131.1 |
| Lg | CFL | 2021 | LUZARDO,Jesus | HVL | 28 | 5 | 16 | 143.1 |
| Lg | GSL | 2005 | BACKE,Brandon | ALR | 31 | 5 | 20 | 156.2 |
| Lg | GSL | 2006 | ARMAS,Tony | ALR | 26 | 3 | 19 | 150.0 |
| Lg | GSL | 2007 | ROBERTSON,Nate | BAL | 42 | 4 | 19 | 190.2 |
| Lg | GSL | 2007 | ZAMBRANO,Carlos | MBS | 36 | 7 | 19 | 217.1 |
| Lg | GSL | 2008 | RICHARD,Clayton | SES | 30 | 5 | 18 | 152.2 |
| Lg | GSL | 2009 | DAVIS,Doug | MC | 32 | 4 | 22 | 184.1 |
| Lg | GSL | 2010 | DEMPSTER,Ryan | ARC | 33 | 10 | 18 | 214.1 |
| Lg | GSL | 2011 | CAPUANO,Chris | ARC | 32 | 6 | 21 | 187.1 |
| Lg | GSL | 2012 | BECKETT,Josh | MBS | 29 | 5 | 18 | 183.1 |
| Lg | GSL | 2013 | SABATHIA,C.C. | ARC | 33 | 5 | 20 | 191.1 |
| Lg | GSL | 2014 | COSART,Jarred | ARC | 32 | 6 | 19 | 205.0 |
| Lg | GSL | 2015 | MILLER,Shelby | BA | 34 | 12 | 17 | 235.0 |
| Lg | GSL | 2016 | EFLIN,Zach | BA | 32 | 3 | 19 | 166.2 |
| Lg | GSL | 2017 | NOVA,Ivan | CSK | 31 | 8 | 19 | 177.1 |
| Lg | GSL | 2018 | TAILLON,Jameson | HTA | 33 | 12 | 20 | 202.1 |
| Lg | GSL | 2019 | PORCELLO,Rick | BE | 33 | 4 | 19 | 184.1 |
| Lg | GSL | 2019 | GRAY,Jon | BA | 31 | 7 | 19 | 163.2 |
| Lg | GSL | 2020 | KUHL,Chad | HUM | 24 | 4 | 16 | 124.2 |
| Lg | GSL | 2020 | EFLIN,Zach | CRS | 32 | 7 | 16 | 175.2 |
| Lg | GSL | 2021 | CROWE,Wil | BA | 35 | 6 | 17 | 178.2 |