50 pitchers are tied for the best K/9 by a relief pitcher in a season, with 27.00 per nine innings. The first three are Joe La Sorsa and Yunior Marte this season and Jayvien Sandridge in 2025.
| NAME | K/9 | SEASON | TM | G | W | L | W% | GS | ERA | SO | CG | SHO | SV | IP | H | ER | R | HR | BB | HBP | GF | IBB | TBF | WP | BB/9 | K/BB | HR/9 | K% | BB% | WHIP | BABIP | RA | H/9 | ||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 |  | J. La Sorsa | 27.00 | 2026 | 1 | 0 | 0 | 0 | 27.00 | 1 | 0 | 0 | 0 | 0.1 | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 0 | 2 | 0 | 0.00 | 27.00 | 50.0 | 0.0 | 3.00 | 27.00 | 27.00 | ||||
| 2 | | Y. Marte | 27.00 | 2026 | 1 | 0 | 0 | 0 | 108.00 | 1 | 0 | 0 | 0 | 0.1 | 3 | 4 | 4 | 0 | 1 | 1 | 0 | 1 | 6 | 0 | 27.00 | 1.00 | 0.00 | 16.7 | 16.7 | 12.00 | 1.000 | 108.00 | 81.00 | ||
| 3 | | J. Sandridge | 27.00 | 2025 | 1 | 0 | 0 | 0 | 27.00 | 2 | 0 | 0 | 0 | 0.2 | 1 | 2 | 2 | 1 | 2 | 1 | 0 | 0 | 6 | 0 | 27.00 | 1.00 | 13.50 | 33.3 | 33.3 | 4.50 | 27.00 | 13.50 | |||
| 4 |  | W. Warren | 27.00 | 2024 | 1 | 0 | 0 | 0 | 27.00 | 3 | 0 | 0 | 0 | 1.0 | 2 | 3 | 3 | 1 | 1 | 0 | 1 | 0 | 6 | 0 | 9.00 | 3.00 | 9.00 | 50.0 | 16.7 | 3.00 | 1.000 | 27.00 | 18.00 | ||
| 5 | | E. Justice | 27.00 | 2024 | 1 | 0 | 0 | 0 | 0.00 | 1 | 0 | 0 | 0 | 0.1 | 0 | 0 | 0 | 0 | 1 | 0 | 1 | 0 | 2 | 0 | 27.00 | 1.00 | 0.00 | 50.0 | 50.0 | 3.00 | 0.00 | 0.00 | |||
| 6 | | C. Andrews | 27.00 | 2024 | 1 | 0 | 0 | 0 | 27.00 | 1 | 0 | 0 | 0 | 0.1 | 1 | 1 | 1 | 1 | 0 | 1 | 0 | 0 | 3 | 0 | 0.00 | 27.00 | 33.3 | 0.0 | 3.00 | 27.00 | 27.00 | ||||
| 7 | | R. Gonzalez | 27.00 | 2021 | 1 | 0 | 0 | 0 | 0.00 | 1 | 0 | 0 | 0 | 0.1 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 1 | 0 | 0.00 | 0.00 | 100.0 | 0.0 | 0.00 | 0.00 | 0.00 | ||||
| 8 | | K. Quackenbush | 27.00 | 2021 | 1 | 0 | 0 | 0 | 27.00 | 1 | 0 | 0 | 0 | 0.1 | 3 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 4 | 0 | 0.00 | 0.00 | 25.0 | 0.0 | 9.00 | 1.000 | 27.00 | 81.00 | |||
| 9 | | N. Maton | 27.00 | 2021 | 1 | 0 | 0 | 0 | 0.00 | 1 | 0 | 0 | 0 | 0.1 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 1 | 0 | 0.00 | 0.00 | 100.0 | 0.0 | 0.00 | 0.00 | 0.00 | ||||
| 10 | | M. Freeman | 27.00 | 2021 | 1 | 0 | 0 | 0 | 0.00 | 1 | 0 | 0 | 0 | 0.1 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 1 | 0 | 0.00 | 0.00 | 100.0 | 0.0 | 0.00 | 0.00 | 0.00 | ||||
| 11 | | W. Crowe | 27.00 | 2021 | 1 | 0 | 0 | 0 | 13.50 | 2 | 0 | 0 | 0 | 0.2 | 1 | 1 | 1 | 0 | 2 | 0 | 0 | 0 | 5 | 2 | 27.00 | 1.00 | 0.00 | 40.0 | 40.0 | 4.50 | 1.000 | 13.50 | 13.50 | ||
| 12 | | C. Roe | 27.00 | 2021 | 1 | 0 | 0 | 0 | 27.00 | 2 | 0 | 0 | 0 | 0.2 | 1 | 2 | 2 | 0 | 1 | 0 | 0 | 0 | 4 | 0 | 13.50 | 2.00 | 0.00 | 50.0 | 25.0 | 3.00 | 1.000 | 27.00 | 13.50 | ||
| 13 |  | F. Peralta | 27.00 | 2021 | 1 | 0 | 0 | 0 | 0.00 | 6 | 0 | 0 | 0 | 2.0 | 2 | 0 | 0 | 0 | 3 | 0 | 0 | 0 | 11 | 0 | 13.50 | 2.00 | 0.00 | 54.5 | 27.3 | 2.50 | 1.000 | 0.00 | 9.00 | ||
| 14 | | M. Brosseau | 27.00 | 2020 | 1 | 0 | 0 | 0 | 0.00 | 1 | 0 | 0 | 0 | 0.1 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 1 | 0 | 0.00 | 0.00 | 100.0 | 0.0 | 0.00 | 0.00 | 0.00 | ||||
| 15 | | J. Beasley | 27.00 | 2020 | 1 | 0 | 0 | 0 | 0.00 | 1 | 0 | 0 | 0 | 0.1 | 2 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 3 | 0 | 0.00 | 0.00 | 33.3 | 0.0 | 6.00 | 1.000 | 0.00 | 54.00 | |||
| 16 | | T. Kahnle | 27.00 | 2020 | 1 | 0 | 0 | 0 | 0.00 | 3 | 0 | 0 | 0 | 1.0 | 1 | 0 | 0 | 0 | 1 | 0 | 0 | 1 | 6 | 0 | 9.00 | 3.00 | 0.00 | 50.0 | 16.7 | 2.00 | .500 | 0.00 | 9.00 | ||
| 17 | | D. Betances | 27.00 | 2019 | 1 | 0 | 0 | 0 | 0.00 | 2 | 0 | 0 | 0 | 0.2 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 2 | 0 | 0.00 | 0.00 | 100.0 | 0.0 | 0.00 | 0.00 | 0.00 | ||||
| 18 | | J. Castillo | 27.00 | 2019 | 1 | 0 | 0 | 0 | 0.00 | 2 | 0 | 0 | 0 | 0.2 | 0 | 0 | 0 | 0 | 1 | 1 | 0 | 0 | 4 | 1 | 13.50 | 2.00 | 0.00 | 50.0 | 25.0 | 1.50 | 0.00 | 0.00 | |||
| 19 | | A. Wojciechowski | 27.00 | 2019 | 1 | 0 | 0 | 0 | 0.00 | 2 | 0 | 0 | 0 | 0.2 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 3 | 1 | 0.00 | 0.00 | 66.7 | 0.0 | 1.50 | 1.000 | 0.00 | 13.50 | |||
| 20 | | J. Gyorko | 27.00 | 2019 | 1 | 0 | 0 | 0 | 0.00 | 1 | 0 | 0 | 0 | 0.1 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 1 | 0 | 0.00 | 0.00 | 100.0 | 0.0 | 0.00 | 0.00 | 0.00 | ||||
| 21 | | A. Williams | 27.00 | 2019 | 2 | 0 | 0 | 0 | 162.00 | 1 | 0 | 0 | 0 | 0.1 | 5 | 6 | 6 | 2 | 1 | 0 | 0 | 0 | 7 | 0 | 27.00 | 1.00 | 54.00 | 14.3 | 14.3 | 18.00 | 1.000 | 162.00 | 135.00 | ||
| 22 | | A. Sampson | 27.00 | 2018 | 1 | 0 | 0 | 0 | 54.00 | 1 | 0 | 0 | 0 | 0.1 | 4 | 2 | 3 | 1 | 0 | 0 | 0 | 0 | 6 | 0 | 0.00 | 27.00 | 16.7 | 0.0 | 12.00 | .750 | 81.00 | 108.00 | |||
| 23 | | D. Valencia | 27.00 | 2018 | 1 | 0 | 0 | 0 | 0.00 | 1 | 0 | 0 | 0 | 0.1 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 1 | 0 | 0.00 | 0.00 | 100.0 | 0.0 | 0.00 | 0.00 | 0.00 | ||||
| 24 | | J. Bleich | 27.00 | 2018 | 2 | 0 | 0 | 0 | 54.00 | 1 | 0 | 0 | 0 | 0.1 | 2 | 2 | 2 | 0 | 0 | 1 | 0 | 0 | 4 | 0 | 0.00 | 0.00 | 25.0 | 0.0 | 6.00 | 1.000 | 54.00 | 54.00 | |||
| 25 | | R. Elias | 27.00 | 2017 | 1 | 0 | 0 | 0 | 0.00 | 1 | 0 | 0 | 0 | 0.1 | 0 | 0 | 0 | 0 | 1 | 0 | 1 | 0 | 2 | 0 | 27.00 | 1.00 | 0.00 | 50.0 | 50.0 | 3.00 | 0.00 | 0.00 | |||
BOS
CIN
NYY
COL
CWS
LAD
PHI
PIT
TBR
MIL
ARI
SDP
BAL
STL
WSH
TEX
OAKStatMuse has game-level data for K/9 going back to the 1901 season.
Some of the information used here was obtained free of charge from Retrosheet.
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More Red Sox Stats
Team Batting Leaders 
HR
22
Contreras
RBI
66
Contreras
AVG
.289
Contreras
Team Pitching Leaders 
W
12
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K
97
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2.35
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HR
95
28th
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419
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844
15th
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3.55
3rd
Blue Jays
MLB 2026 Batting Leaders
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MLB 2026 Standings
| NL East | W | L | PCT | GB |
|---|---|---|---|---|
58 | 41 | .586 | ||
56 | 45 | .554 | 3.0 | |
52 | 49 | .515 | 7.0 | |
51 | 50 | .505 | 8.0 | |
42 | 59 | .416 | 17.0 | |
| NL Central | W | L | PCT | GB |
63 | 37 | .630 | ||
56 | 44 | .560 | 7.0 | |
51 | 47 | .520 | 11.0 | |
52 | 49 | .515 | 11.5 | |
45 | 53 | .459 | 17.0 | |
| NL West | W | L | PCT | GB |
63 | 38 | .624 | ||
51 | 48 | .515 | 11.0 | |
49 | 51 | .490 | 13.5 | |
42 | 58 | .420 | 20.5 | |
40 | 62 | .392 | 23.5 |
Braves
Marlins
Mets
Cubs
Diamondbacks
Padres
Giants| AL East | W | L | PCT | GB |
|---|---|---|---|---|
57 | 42 | .576 | ||
56 | 44 | .560 | 1.5 | |
51 | 48 | .515 | 6.0 | |
49 | 52 | .485 | 9.0 | |
46 | 54 | .460 | 11.5 | |
| AL Central | W | L | PCT | GB |
53 | 46 | .535 | ||
53 | 48 | .525 | 1.0 | |
49 | 52 | .485 | 5.0 | |
47 | 53 | .470 | 6.5 | |
41 | 60 | .406 | 13.0 | |
| AL West | W | L | PCT | GB |
50 | 50 | .500 | ||
50 | 50 | .500 | ||
48 | 54 | .471 | 3.0 | |
42 | 57 | .424 | 7.5 | |
39 | 61 | .390 | 11.0 |
Guardians
Twins
Tigers
Royals
Mariners
Astros
Angels