With the trade of Jon Lester to Oakland this past week, so departs one of the best left-handed starting pitchers in Red Sox team history, with 110 wins, a no-hitter, and two World Series championships to his credit. Among southpaws in team history, his 110 wins is second-most behind the legendary Mel Parnell and his 1386 strikeouts leads all others.
There is no question from anyone who has watched him over his eight-plus seasons with Boston that he has been an invaluable contributor to its recent success and there’s a possibility that we have not seen him pitch for the last time in a Red Sox uniform. So how does he compare to others greats who have pitched for this franchise?
In franchise history, there have been 133 lefties who have started at least one game for the Red Sox. We looked at Baseball-Reference.com‘s Play Index and narrowed the search to those pitchers who toed the rubber for at least 100 games with Boston as a starter.
Top Career ERA+
| Rk | Player | ERA+ | GS | G | CG | SHO | GF | W | L | W-L% | IP | SO | ERA |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | Lefty Grove | 143 | 190 | 214 | 119 | 15 | 17 | 105 | 62 | .629 | 1539.2 | 743 | 3.34 |
| 2 | Dutch Leonard | 129 | 161 | 211 | 96 | 25 | 40 | 90 | 64 | .584 | 1361.1 | 771 | 2.13 |
| 3 | Babe Ruth | 125 | 143 | 158 | 105 | 17 | 11 | 89 | 46 | .659 | 1190.1 | 483 | 2.19 |
| 4 | Mel Parnell | 125 | 232 | 289 | 113 | 20 | 36 | 123 | 75 | .621 | 1752.2 | 732 | 3.50 |
| 5 | Jon Lester | 120 | 241 | 242 | 10 | 3 | 0 | 110 | 63 | .636 | 1519.1 | 1386 | 3.64 |
| 6 | Ray Collins | 116 | 151 | 199 | 90 | 19 | 36 | 84 | 62 | .575 | 1336.0 | 511 | 2.51 |
Top Career WAR
| Rk | Player | WAR | GS | G | CG | SHO | W | L | W-L% | IP | SO | ERA |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | Lefty Grove | 44.7 | 190 | 214 | 119 | 15 | 105 | 62 | .629 | 1539.2 | 743 | 3.34 |
| 2 | Jon Lester | 31.0 | 241 | 242 | 10 | 3 | 110 | 63 | .636 | 1519.1 | 1386 | 3.64 |
| 3 | Mel Parnell | 27.4 | 232 | 289 | 113 | 20 | 123 | 75 | .621 | 1752.2 | 732 | 3.50 |
| 4 | Dutch Leonard | 27.2 | 161 | 211 | 96 | 25 | 90 | 64 | .584 | 1361.1 | 771 | 2.13 |
| 5 | Ray Collins | 23.1 | 151 | 199 | 90 | 19 | 84 | 62 | .575 | 1336.0 | 511 | 2.51 |
| 6 | Babe Ruth | 20.8 | 143 | 158 | 105 | 17 | 89 | 46 | .659 | 1190.1 | 483 | 2.19 |
Top Career WHIP
| Rk | Player | WHIP | GS | G | CG | SHO | W | L | W-L% | IP | SO | ERA |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | Jesse Tannehill | 1.118 | 106 | 116 | 85 | 14 | 62 | 38 | .620 | 885.2 | 342 | 2.50 |
| 2 | Ray Collins | 1.134 | 151 | 199 | 90 | 19 | 84 | 62 | .575 | 1336.0 | 511 | 2.51 |
| 3 | Dutch Leonard | 1.136 | 161 | 211 | 96 | 25 | 90 | 64 | .584 | 1361.1 | 771 | 2.13 |
| 4 | Babe Ruth | 1.142 | 143 | 158 | 105 | 17 | 89 | 46 | .659 | 1190.1 | 483 | 2.19 |
| 5 | Jon Lester | 1.287 | 241 | 242 | 10 | 3 | 110 | 63 | .636 | 1519.1 | 1386 | 3.64 |
| 6 | Lefty Grove | 1.321 | 190 | 214 | 119 | 15 | 105 | 62 | .629 | 1539.2 | 743 | 3.34 |
Grove, who is the only pitcher to notch his 300th victory in a Red Sox uniform, pitched eight seasons between 1934 and 1941. His ERA+ of 134 and WAR of 44.7 leads the franchise in both categories for left-handed pitchers. He is also sixth all-time in WHIP. Leonard, who pitched six seasons between 1913 and 1918 and was part of three World Series championships, has the second-best ERA+ in franchise history (134), is fourth in WAR (27.2), and third in WHIP (1.136), putting him very close to Grove.
Also showing up on all three lists is Ruth who, while better known for changing the game of baseball with his bat, was part of the same three world championships as Leonard and has the third-best ERA+ in franchise history for southpaws. Collins, while perhaps not as well-known to casual Red Sox fans, is also on all three lists, playing for two world champions in 1912 and 1915 and currently sitting at number two in franchise history for WHIP (1.134).
Lester, upon close examination, certainly matches well in all three categories. His ERA+ of 120 places him fifth behind Ruth, his WAR of 31.0 places him second only to Grove, and his WHIP puts him fifth in that category. Also consider that, save for Collins and Tannehill, every other player listed here is a member of the Boston Red Sox Hall of Fame, and it’s probably a safe bet to say that he will someday be there, too.