Zack Kelly
Zack Kelly is a 31-year-old relief pitcher for the Boston Red Sox. He is a power relief pitcher, ranked 1955th in the league at the role.
About these ratings
Tool ratings combine recorded performance with statistical estimates. Speed, arm, and fielding include outcome-based estimates rather than direct physical measurements.
Limited MLB evidence: 51.8% MLB and 48.2% level-adjusted minor-league estimate.
Minor-league valuation uses season-decayed historical statistics because the current-season sample is limited.
Minor-league estimate: 28.8% observed statistical weight and 71.2% historical peer baseline; individual tools use their own sample weights.
* On NTV, this indicates estimated or unverified inputs. CE uses an asterisk only when current contract information is unavailable.
CE uses the best available contract information, including partial terms, estimated salaries, and projected team control. CE shows an asterisk only when current contract information is unavailable; free agents without a current agreement use 100*.
2026 win contribution
0.46 Player Wins · 0.34 expected from replacement · 0.11 wins above replacement
Includes contributions to every team played for in 2026. Perf expresses wins above replacement on a scale where 100 is average. How the win totals reconcile
Six-tool graphs show percentiles from available performance evidence. Speed uses baserunning outcomes; Arm uses position-adjusted throwing outcomes. Movement describes tracked pitch movement within pitch type. Minor-league comparisons account for competition level; unavailable measurements display MD.
Edge Profile
Edge combines Perf, Stick, and Carry to show how valuable a player is right now. With a Perf of 87, Stick of 93, and Carry of 90, Zack Kelly sits in the 50th percentile, 41st percentile, and 44th percentile in those areas. His 76 Edge lands in the 35th percentile and ranks 324th among relief pitchers.
Stick Profile
Stick looks beyond the immediate results and estimates what should hold over a larger sample. Zack Kelly's 93 Stick suggests he is performing close to the level supported by his underlying profile. It also places him in the 41st percentile and ranks 453rd among relief pitchers.
Perf Profile
Perf measures season wins above replacement after allocating each team's actual wins to its players. It includes Zack Kelly's contributions to every team he played for. His 87 Perf is below average on a scale where 100 is average and 20 points is one standard deviation. It sits in the 50th percentile and ranks 266th among relief pitchers.
Carry Profile
Carry places Perf in the context of the roster around a player and includes a bounded clutch adjustment for offense, pitching, and defense when available. Close games and later innings earn more weight, and difficult defensive plays receive their own credit. His clutch runs are offense +0.0, pitching -0.8, defense -0.5. The strongest rated teammates are Wilyer Abreu at 140, Willson Contreras at 131, and Payton Tolle at 118. Zack Kelly has contributed about as much as his own Perf suggests, resulting in a Carry of 90.
LI Profile
LI looks at how much useful baseball a player may still have ahead of him. At age 31, Zack Kelly carries a 97 LI, which points to a steady near-term outlook without a major longevity advantage. That places him in the 3rd percentile and ranks 3342nd among relief pitchers.
CE Profile
CE compares expected production with the money and years attached to a contract. The model uses a 2 seasons control horizon, $0.8 million average annual value, and about $0.8 million in contract-scenario costs for Zack Kelly. Options and arbitration can make those years or costs conditional; manual contract inputs may lag new agreements. His 102 CE is close to a fair exchange between salary and production, placing him in the 29th percentile and 2518th among relief pitchers.
NTV Profile
NTV estimates Zack Kelly's value on a neutral trade market before the needs of a specific club are considered. His +4* NTV reflects his present ability, expected future value, age, contract, control, positional demand, and risk. That mark sits in the 36th percentile and ranks 1955th among relief pitchers. Zack Kelly has modest positive value, though the market return would depend heavily on fit and demand.