Isaac Mattson

Isaac Mattson

29-Year-Old PitcherRP
Pittsburgh Pirates AAA
2025 Fantasy Outlook
There was no outlook written for Isaac Mattson in 2025. Check out the latest news below for more on his current fantasy value.
$Signed a one-year contract with the Pirates in December of 2024.
Optioned to Triple-A
PPittsburgh Pirates  AAA
May 26, 2025
The Pirates optioned Mattson to Triple-A Indianapolis on Monday, Noah Hiles of the Pittsburgh Post-Gazette reports.
ANALYSIS
The move makes room on the 26-man roster for Braxton Ashcraft, who was recalled from Triple-A on Monday. Mattson appeared in three major-league games for the Pirates since being promoted to the majors this past Tuesday and allowed one run on one hit and one walk while striking out four across three innings. He'll head back to Triple-A, where he has a 2.33 ERA, 0.94 WHIP, four saves and a 24:5 K:BB across 19.1 innings.
Read More News
Pitching Stats
Loading Pitching Stats...
2025
2024
2021
2025 MLB Game Log
calculator icon
Calculate Stats Over Time
Just click on any two dates.
Scoring
FanDuel
DraftKings
Yahoo DFS
Sorare
Loading Pitching Game Log...
2024 MLB Game Log
calculator icon
Calculate Stats Over Time
Just click on any two dates.
Scoring
FanDuel
DraftKings
Yahoo DFS
Sorare
Loading Pitching Game Log...
2021 MLB Game Log
calculator icon
Calculate Stats Over Time
Just click on any two dates.
Scoring
FanDuel
DraftKings
Yahoo DFS
Sorare
Loading Pitching Game Log...
Minor League Game Log
calculator icon
Calculate Stats Over Time
Just click on any two dates.
Loading Minor League Pitching Game Log...
Pitching Appearances Breakdown
Average Pitch Count
16
Last 10 Games
16
Last 5 Games
16
How many pitches does Isaac Mattson 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+
 
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+
 
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 Isaac Mattson generally pitch?
 
 
 
1st
 
 
 
2nd
 
 
 
3rd
 
 
 
4th
 
 
 
5th
 
 
 
6th
 
 
 
7th
 
 
 
8th
 
 
 
9th
 
Extra
 
 
 
1st
 
 
 
2nd
 
 
 
3rd
 
 
 
4th
 
 
 
5th
 
 
 
6th
 
 
 
7th
 
 
 
8th
 
 
 
9th
 
Extra
 
 
 
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
 
 
-8%
BAA vs RHP
2025
 
 
-100%
BAA vs RHP
2024
 
 
-100%
BAA vs LHP
2023
No Stats
BAA Batters K BB H 2B 3B HR
Since 2023vs Left .077 14 7 1 1 0 0 1
Since 2023vs Right .071 20 3 5 1 0 0 0
2025vs Left .250 4 3 0 1 0 0 1
2025vs Right .000 7 1 1 0 0 0 0
2024vs Left .000 10 4 1 0 0 0 0
2024vs Right .125 13 2 4 1 0 0 0
2023vs Left 0 0 0 0 0 0 0 0
2023vs Right 0 0 0 0 0 0 0 0
Home/Away Pitching Splits
Since 2023
 
 
-100%
ERA on Road
2025
 
 
-100%
ERA on Road
2024
 
 
-100%
ERA on Road
2023
No Stats
ERA WHIP IP W L SV K/9 BB/9 HR/9
Since 2023Home 8.31 1.62 4.1 0 0 0 10.4 10.4 2.1
Since 2023Away 0.00 0.25 4.0 0 0 0 11.3 2.3 0.0
2025Home 3.00 0.67 3.0 0 0 0 12.0 3.0 3.0
2025Away 0 0 0 0 0 0 0 0 0
2024Home 20.25 3.75 1.1 0 0 0 6.8 27.0 0.0
2024Away 0.00 0.25 4.0 0 0 0 11.3 2.3 0.0
2023Home 0 0 0 0 0 0 0 0 0
2023Away 0 0 0 0 0 0 0 0 0
Minor League Left/Right Pitching Splits (AAA)
Since 2023
 
 
-3%
BAA vs LHP
2025
 
 
-26%
BAA vs RHP
2024
 
 
-12%
BAA vs LHP
2023
No Stats
BAA Batters K BB H 2B 3B HR
Since 2023vs Left .198 140 48 17 24 4 1 2
Since 2023vs Right .205 187 50 21 33 7 1 5
2025vs Left .214 30 12 1 6 0 1 1
2025vs Right .158 42 10 4 6 1 0 0
2024vs Left .194 110 36 16 18 4 0 1
2024vs Right .220 145 40 17 27 6 1 5
2023vs Left 0 0 0 0 0 0 0 0
2023vs Right 0 0 0 0 0 0 0 0
Stat Review
How does Isaac Mattson 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.
  • K/BB
    Strikeout to walk ratio.
  • K/9
    Average strikeouts per nine innings.
  • BB/9
    Average walks per nine innings.
  • HR/9
    Average home runs allowed per nine innings.
  • Fastball
    Average fastball velocity.
  • ERA
    Earned run average. The average earned runs allowed per nine innings.
  • WHIP
    Walks plus hits per inning pitched.
  • BABIP
    Batting average on balls in play. Measures how many balls in play against a pitcher go for hits.
  • GB/FB
    Groundball to flyball ratio. The higher the number, the more likely a pitcher is to induce groundballs.
  • Left On Base
    The percentage of base runners that a pitcher strands on base over the course of a season.
  • Exit Velocity
    The speed of the baseball as it comes off the bat, immediately after a batter makes contact.
  • Barrels/BBE
    The percentage of batted ball events resulting in a Barrel. A Barrel is a batted ball with similar exit velocity and launch angle to past ones that led to a minimum .500 batting average and 1.500 slugging percentage.
  • Spin Rate
    Spin Rate is the rate of spin on a baseball after it is released. It is measured in revolutions per minute (rpm).
  • Balls Hit 95+ MPH
    The percentage of batted balls hit that met or exceeded the 95 MPH threshold.
  • Swinging Strike
    The percentage of pitches that result in a swing and a miss.
K/BB
4.00
 
K/9
12.0
 
BB/9
3.0
 
HR/9
3.0
 
Fastball
92.1 mph
 
ERA
3.00
 
WHIP
0.67
 
BABIP
.000
 
GB/FB
0.20
 
Left On Base
166.7%
 
Exit Velocity
86.5 mph
 
Barrels/BBE
20.0%
 
Spin Rate
2060 rpm
 
Balls Hit 95+ MPH
30.0%
 
Swinging Strike
14.9%
 
Advanced Pitching Stats
Loading Advanced Pitching Stats...
Defensive Stats
Loading MLB Defensive Stats...
Stats Vs Today's Lineup
Want more matchup stats?
Loading Matchup Stats...
Our full team depth charts are reserved for RotoWire subscribers.
Subscribe Now
More Fantasy News
Promoted Tuesday
PPittsburgh Pirates  AAA
May 20, 2025
The Pirates selected Mattson from Triple-A Indianapolis on Tuesday.
ANALYSIS
Subscribe now to instantly reveal our take on this news.
Returns to Pittsburgh
PPittsburgh Pirates  AAA
December 5, 2024
Mattson signed a minor-league contract with the Pirates on Thursday, Noah Hiles of the Pittsburgh Post-Gazette reports.
ANALYSIS
Subscribe now to instantly reveal our take on this news.
Removed from 40-man roster
PPittsburgh Pirates  AAA
November 4, 2024
The Pirates outrighted Mattson to Triple-A Indianapolis on Monday, Andrew Destin of the Pittsburgh Post-Gazette reports.
ANALYSIS
Subscribe now to instantly reveal our take on this news.
Selected from Triple-A
PPittsburgh Pirates  AAA
September 19, 2024
The Pirates selected Mattson was selected from Triple-A Indianapolis on Thursday, Noah Hiles of the Pittsburgh Post-Gazette reports.
ANALYSIS
Subscribe now to instantly reveal our take on this news.
Heads to Pirates on MiLB deal
PPittsburgh Pirates  AAA
December 20, 2023
Mattson signed a minor-league contract with the Pirates on Dec. 11.
ANALYSIS
Subscribe now to instantly reveal our take on this news.
Latest Fantasy Rumors
Joining MLB roster?
PPittsburgh Pirates  AAA
May 20, 2025
Mattson has a locker in the Pirates clubhouse ahead of Tuesday's game versus the Reds, reports Noah Hiles of the Pittsburgh Post-Gazette.
ANALYSIS
The right-hander re-signed with the Pirates on a minor-league contract in December, and it appears he'll be added to the MLB roster Tuesday. Mattson has a 2.33 ERA, 0.94 WHIP and 24:5 K:BB across 19.1 innings for Triple-A Indianapolis this year.
See All MLB Rumors