2025 Stats
W-L
1-4
ERA
3.47
WHIP
0.90
K
16
SV
3
Rest-of-Season Projections
2025 Fantasy Outlook
Slaten, a 2019 draft pick by the Rangers, was selected by the Mets during the Rule 5 Draft last offseason. The 26-year-old was subsequently traded to Boston and impressed his new club during Grapefruit League play, flashing upper-90's velocity. Unsurprisingly, he made the Red Sox Opening Day roster and remained with the team all year. Slaten was an immediate fixture in Boston's high-leverage hierarchy, mixing four pitches effectively to a 2.93 ERA, 1.01 WHIP and 58:9 K:BB across 55.1 frames. The rookie right-hander recorded 10 or more strikeouts on all four of his offerings, including 18 apiece on his four-seamer and sweeper. Elbow inflammation cost Slaten a month-and-a-half last summer, but it's exciting to think about what he could offer in a full season. Red Sox manager Alex Cora said in the past that he envisions Slaten as a potential long-term closer option and he certainly has the talent to emerge out of a save share with Liam Hendriks and Aroldis Chapman in 2025. Read Past Outlooks
Extends scoreless stretch
Slaten retired all five batters faced to earn a hold in Tuesday's 2-0 win over the Mets.
ANALYSIS
Slaten entered the middle of the seventh inning with a runner at first base and induced a double-play grounder to squelch the threat. He then got three harmless groundouts in the eighth. Slaten endured a three-game hiccup at the end of April/beginning of May (six runs, 2.1 innings), but the right-hander has been on point since. Tuesday's work extended a scoreless streak to 7.2 innings, during which he hasn't allowed a hit or a walk.
Slaten entered the middle of the seventh inning with a runner at first base and induced a double-play grounder to squelch the threat. He then got three harmless groundouts in the eighth. Slaten endured a three-game hiccup at the end of April/beginning of May (six runs, 2.1 innings), but the right-hander has been on point since. Tuesday's work extended a scoreless streak to 7.2 innings, during which he hasn't allowed a hit or a walk.
Pitching Stats
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2025
2024
Minor League Game Log
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Pitching Appearances Breakdown
Average Pitch Count
14
Last 10 Games
14
Last 5 Games
15
How many pitches does Justin Slaten generally throw?
1-10
11-20
21-30
31-40
41-50
51-60
61-70
71-80
81-90
91-100
101-110
111-120
121+
What part of the game does Justin Slaten generally pitch?
1st
2nd
3rd
4th
5th
6th
7th
8th
9th
Extra
% Games Reaching Innings Threshold
% Games By Number of Innings Pitched
Left/Right Pitching Splits
Since 2023
-29%
BAA vs LHP
2025
-39%
BAA vs LHP
| BAA | K | BB | H | HR | ||||
|---|---|---|---|---|---|---|---|---|
| Since 2023vs Left | .170 | 38 | 13 | 23 | 2 | |||
| Since 2023vs Right | .241 | 36 | 3 | 38 | 3 | |||
| 2025vs Left | .128 | 7 | 5 | 5 | 0 | |||
| 2025vs Right | .209 | 9 | 2 | 9 | 1 | |||
| 2024vs Left | .188 | 31 | 8 | 18 | 2 | |||
| 2024vs Right | .252 | 27 | 1 | 29 | 2 | |||
| 2023vs Left | 0 | 0 | 0 | 0 | 0 | |||
| 2023vs Right | 0 | 0 | 0 | 0 | 0 | |||
| More Splits→ | View More Split Stats | |||||||
Home/Away Pitching Splits
Since 2023
-59%
ERA at Home
2025
-68%
ERA at Home
| ERA | WHIP | IP | K/9 | BB/9 | |||||
|---|---|---|---|---|---|---|---|---|---|
| Since 2023Home | 1.73 | 0.77 | 36.1 | 7.4 | 1.2 | ||||
| Since 2023Away | 4.25 | 1.16 | 42.1 | 9.4 | 2.3 | ||||
| 2025Home | 1.64 | 0.55 | 11.0 | 4.9 | 0.8 | ||||
| 2025Away | 5.11 | 1.22 | 12.1 | 7.3 | 4.4 | ||||
| 2024Home | 1.78 | 0.87 | 25.1 | 8.5 | 1.4 | ||||
| 2024Away | 3.90 | 1.13 | 30.0 | 10.2 | 1.5 | ||||
| 2023Home | 0 | 0 | 0 | 0 | 0 | ||||
| 2023Away | 0 | 0 | 0 | 0 | 0 | ||||
| More Splits→ | View More Split Stats | ||||||||
Stat Review
How does Justin Slaten compare to other relievers?
This section compares his stats with all relief pitcher seasons from the previous three seasons (minimum 30 innings)*. The bar represents the player's percentile rank. For example, if the bar is halfway across, then the player falls into the 50th percentile for that stat and it would be considered average.
* Exit Velocity, Barrels/BBE %, Balls Hit 95+ MPH %, and Spin Rate are benchmarked against 2019 data (min 30 IP). See here for more exit velocity/barrels stats plus an explanation of current limitations with that data set.
* Exit Velocity, Barrels/BBE %, Balls Hit 95+ MPH %, and Spin Rate are benchmarked against 2019 data (min 30 IP). See here for more exit velocity/barrels stats plus an explanation of current limitations with that data set.
K/BB
2.29K/9
6.2BB/9
2.7HR/9
0.4Fastball
97.1 mphERA
3.47WHIP
0.90BABIP
.207GB/FB
1.04Left On Base
45.9%Exit Velocity
81.6 mphBarrels/BBE
3.8%Spin Rate
2563 rpmBalls Hit 95+ MPH
17.0%Swinging Strike
11.8%Advanced Pitching Stats
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Defensive Stats
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Stats Vs Today's Lineup
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More Fantasy News
Blows save, takes loss Thursday
Slaten (0-2) was charged with the loss and a blown save in Thursday's 4-2 defeat to the Blue Jays, allowing three runs on three hits and one walk with no strikeouts in one inning.
ANALYSIS
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Notches third save
Slaten picked up the save in Monday's 4-2 win against the White Sox, pitching a clean inning with one strikeout.
ANALYSIS
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Slams door for second save
Slaten earned the save after throwing a clean ninth inning in Wednesday's win over the Rays. He struck out two.
ANALYSIS
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Notches save in opener
Slaten struck out one and didn't allow a baserunner in a scoreless ninth inning to earn the save Thursday against the Rangers.
ANALYSIS
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Works scoreless inning
Slaten allowed a hit and struck out two over a scoreless inning in Friday's spring game against Miami.
ANALYSIS
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