Zack Kelly

Zack Kelly

29-Year-Old PitcherRP
Boston Red Sox AAA
2025 Fantasy Outlook
There was no outlook written for Zack Kelly in 2025. Check out the latest news below for more on his current fantasy value.
$Signed a one-year contract with the Red Sox in March of 2024.
Sent to minors
PBoston Red Sox  AAA
September 14, 2024
The Red Sox optioned Kelly to Triple-A Worcester on Saturday, Julian McWilliams of The Boston Globe reports.
ANALYSIS
Kelly gave up three earned runs without recording an out during Friday's loss to the Yankees, inflating his ERA to 3.97 across 56.2 innings. He'll now head back to Triple-A, though there's still a possibility he makes another appearance in the majors before the season ends. He'll be joined in Worcester by Cam Booser while Bailey Horn and Zach Penrod come up from the minors to fill the open bullpen spots.
Read More News
Pitching Stats
Loading Pitching Stats...
2024
2023
2022
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...
2023 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...
2022 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
20
Last 10 Games
17
Last 5 Games
16
How many pitches does Zack Kelly 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 Zack Kelly 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 2022
 
 
-12%
BAA vs RHP
2024
 
 
-25%
BAA vs RHP
2023
 
 
-4%
BAA vs RHP
2022
 
 
-31%
BAA vs LHP
BAA Batters K BB H 2B 3B HR
Since 2022vs Left .233 158 33 23 31 7 0 7
Since 2022vs Right .206 185 45 16 34 9 0 5
2024vs Left .242 107 26 15 22 3 0 7
2024vs Right .182 134 35 12 22 5 0 3
2023vs Left .222 24 4 6 4 3 0 0
2023vs Right .214 19 2 2 3 2 0 0
2022vs Left .208 27 3 2 5 1 0 0
2022vs Right .300 32 8 2 9 2 0 2
More Splits View More Split Stats
Home/Away Pitching Splits
Since 2022
 
 
-3%
ERA on Road
2024
 
 
-14%
ERA on Road
2023
 
 
-78%
ERA at Home
2022
 
 
-42%
ERA on Road
ERA WHIP IP W L SV K/9 BB/9 HR/9
Since 2022Home 4.01 1.50 42.2 3 3 0 8.9 5.1 1.1
Since 2022Away 3.89 1.08 37.0 4 0 0 8.8 3.6 1.7
2024Home 4.22 1.44 32.0 2 3 0 9.6 4.8 1.4
2024Away 3.65 1.01 24.2 4 0 0 9.9 3.6 1.8
2023Home 1.59 1.41 5.2 0 0 0 6.4 6.4 0.0
2023Away 7.36 1.91 3.2 0 0 0 4.9 9.8 0.0
2022Home 5.40 2.00 5.0 1 0 0 7.2 5.4 0.0
2022Away 3.12 0.92 8.2 0 0 0 7.3 1.0 2.1
More Splits View More Split Stats
Stat Review
How does Zack Kelly 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
2.26
 
K/9
9.7
 
BB/9
4.3
 
HR/9
1.6
 
Fastball
96.6 mph
 
ERA
3.97
 
WHIP
1.25
 
BABIP
.256
 
GB/FB
1.51
 
Left On Base
70.2%
 
Exit Velocity
80.5 mph
 
Barrels/BBE
6.0%
 
Spin Rate
2407 rpm
 
Balls Hit 95+ MPH
19.3%
 
Swinging Strike
12.1%
 
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
Recent RotoWire Articles Featuring Zack Kelly See More
MLB Bets Today: Expert Picks for Boston Red Sox vs. Houston Astros
134 days ago
Hunter Brown has recorded 11 quality starts in his last 13 starts and faces Boston on Sunday, August 11. John Bollman shares his expert MLB picks and best bets for this Astros-Red Sox contest.
Fantasy Baseball Injury Report: IL List Continues to Mount for Atlanta
154 days ago
Atlanta's injury woes continued over the weekend as Ozzie Albies and Max Fried joined Ronald Acuna, Michael Harris and Spencer Strider on the injured list.
Mound Musings: The Endgame Odyssey Continues – American League
179 days ago
Brad Johnson discusses AL bullpens in which adjustments may still be made, and in Oakland Mason Miller is performing well, but will he still be in town after the trade deadline?
AL FAAB Factor: Waiver Pickups of the Week
183 days ago
Erik Siegrist reviews the latest additions to the AL waiver wire as Ben Rice tries to fill the hole at first base for the Yankees.
2023 Fantasy Outlook
Kelly was a journeyman reliever earlier in his minor-league career. He gained fastball velocity during the off year in 2020 and came back racking up the strikeouts in 2021 and 2022, culminating with him fanning 72 batters (34.4 percent) in 49.2 innings at Triple-A Worcester before earning his MLB debut last season. In addition to his mid-90s fastball, Kelly sports a plus changeup that has similar movement characteristics to Devin Williams' famous "airbender" changeup. Kelly probably won't get saves as a rookie, but he could offer value in leagues where relievers who post good ratios and strikeouts are useful.
More Fantasy News
Bound for Worcester
PBoston Red Sox  AAA
September 13, 2024
The Red Sox will option Kelly to Triple-A Worcester on Saturday, Chris Cotillo of MassLive.com reports.
ANALYSIS
Subscribe now to instantly reveal our take on this news.
Tosses three scoreless frames
PBoston Red Sox  AAA
August 26, 2024
Kelly did not factor in the decision Monday against Toronto after issuing two walks over three scoreless innings as the opener. He struck out four batters during the loss.
ANALYSIS
Subscribe now to instantly reveal our take on this news.
Opening Monday's game
PBoston Red Sox  AAA
August 26, 2024
Kelly will serve as the Red Sox's opening pitcher for Monday's game against the Blue Jays, Mac Cerullo of the Boston Herald reports.
ANALYSIS
Subscribe now to instantly reveal our take on this news.
Coughs up lead
PBoston Red Sox  AAA
July 23, 2024
Kelly allowed two runs (one earned) on one hit while striking out three over two innings in Monday's 9-8 extra-innings loss to Colorado.
ANALYSIS
Subscribe now to instantly reveal our take on this news.
Scoreless outing as opener
PBoston Red Sox  AAA
June 23, 2024
Kelly allowed a hit over 2.2 shutout innings as the opener during Sunday's win over the Reds. He struck out three batters.
ANALYSIS
Subscribe now to instantly reveal our take on this news.
Latest Fantasy Rumors
Should soon return to majors
PBoston Red Sox  AAA
May 28, 2024
Chris Cotillo of The Springfield Republican expects Kelly's stay at Triple-A Worcester to be a short one after being optioned Sunday.
ANALYSIS
The right-hander has a 2.16 ERA and 1.26 WHIP across 16.2 innings for Boston this season, so it's only a matter of time before he's back in the big-league bullpen. Kelly likely won't be in the high-leverage mix for the Red Sox anytime soon, but it's not completely out of the question if the club trades away the likes of Kenley Jansen and Chris Martin, both of whom are pending free agents, this summer.
See All MLB Rumors