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Zack Kelly
Boston Red SoxMLB
ID: 677161
29
Outings
593
Total Pitches
36
Strikeouts
11
Walks
3.27
K/BB
Proprietary Metrics
29 games • 593 pitches
78Tunnel ScoreRelease point similarity81SeparationMovement divergence57Extension ScoreFastball extension & velo jump
What do these metrics mean?
Tunnel Score (0-100): Measures how similar a pitcher's pitches look coming out of the hand before they diverge. Higher scores indicate better deception—the ball looks the same to the batter regardless of pitch type until it's too late.
Separation Score (0-100): Measures how much the pitches diverge at the plate based on horizontal and vertical movement. Higher separation means more contrast between pitch types, making the arsenal harder to square up.
Extension Score (0-100): Measures fastball extension and perceived velocity jump. Higher scores indicate better release extension and effective speed vs release speed, making the fastball appear faster to batters.
Arsenal Over Time
Velocity Over Time
Spin Rate Over Time
All Outings (99)
| Date▲▼ | Opp▲▼ | Pitches▲▼ | Velo▲▼ | K▲▼ | BB▲▼ | SwStr%▲▼ | Tunnel▲▼ | Sep▲▼ | Pair▲▼ |
|---|---|---|---|---|---|---|---|---|---|
| 2025-10-01 | NYY | 6 | 90.8(97.4) | 1 | 0 | 16.7% | - | - | - |
| 2025-09-28 | DET | 6 | 88.2(94.1) | 0 | 0 | 0.0% | - | - | - |
| 2025-09-26 | DET | 17 | 92.4(97.6) | 0 | 0 | 5.9% | 79 | 95 | SI/ST |
| 2025-09-25 | TOR | 10 | 91.7(97.1) | 0 | 0 | 0.0% | 71 | - | - |
| 2025-09-21 | TB | 20 | 90.3(97.1) | 1 | 0 | 15.0% | 74 | 68 | FC/ST |
| 2025-09-19 | TB | 18 | 87.8(96.2) | 0 | 0 | 0.0% | 76 | 90 | FF/ST |
| 2025-09-17 | ATH | 8 | 95.1(97.4) | 1 | 0 | 12.5% | - | - | - |
| 2025-09-16 | ATH | 16 | 90.4(97.0) | 3 | 0 | 25.0% | 76 | 97 | SI/ST |
| 2025-09-12 | NYY | 21 | 90.4(97.2) | 0 | 2 | 4.8% | 75 | 63 | CH/FC |
| 2025-09-08 | ATH | 7 | 91.4(95.5) | 0 | 0 | 14.3% | - | - | - |
| 2025-09-07 | AZ | 16 | 92.4(97.7) | 1 | 1 | 0.0% | 79 | 72 | FC/SI |
| 2025-09-03 | CLE | 63 | 89.5(96.9) | 4 | 0 | 7.9% | 79 | 79 | FF/ST |
| 2025-06-29 | TOR | 28 | 91.4(97.7) | 1 | 1 | 7.1% | 76 | 74 | SI/ST |
| 2025-06-25 | LAA | 31 | 89.5(98.4) | 4 | 0 | 12.9% | 80 | 96 | SI/ST |
| 2025-06-22 | SF | 23 | 90.8(96.5) | 0 | 0 | 4.3% | 81 | 76 | FF/ST |
| 2025-06-20 | SF | 14 | 91.0(97.0) | 2 | 1 | 14.3% | 82 | 83 | SI/ST |
| 2025-06-17 | SEA | 16 | 86.7(96.6) | 2 | 0 | 18.8% | 76 | 100 | CH/ST |
| 2025-06-09 | TB | 27 | 90.9(97.9) | 1 | 2 | 3.7% | 72 | 87 | SI/ST |
| 2025-06-08 | NYY | 9 | 87.2(95.5) | 0 | 0 | 11.1% | - | - | - |
| 2025-06-06 | NYY | 35 | 88.7(97.5) | 4 | 0 | 17.1% | 78 | 87 | CH/ST |
| 2025-06-03 | LAA | 12 | 93.3(96.6) | 0 | 1 | 0.0% | 84 | 42 | FC/FF |
| 2025-05-25 | BAL | 25 | 90.4(97.1) | 0 | 1 | 4.0% | 76 | 82 | FF/ST |
| 2025-04-20 | CWS | 9 | 88.6(94.2) | 0 | 0 | 0.0% | - | - | - |
| 2025-04-15 | TB | 43 | 91.3(96.9) | 4 | 0 | 20.9% | 81 | 76 | FF/ST |
| 2025-04-12 | CWS | 27 | 90.8(97.0) | 3 | 1 | 7.4% | 81 | 80 | FF/ST |
| 2025-04-08 | TOR | 36 | 88.9(95.8) | 2 | 1 | 8.3% | 81 | 79 | CH/ST |
| 2025-04-04 | STL | 22 | 91.5(97.0) | 1 | 0 | 4.5% | 75 | 73 | FF/ST |
| 2025-04-03 | BAL | 5 | 88.6(95.2) | 0 | 0 | 20.0% | - | - | - |
| 2025-03-29 | TEX | 23 | 87.1(96.2) | 1 | 0 | 8.7% | 79 | 100 | FF/ST |
| 2024-09-13 | NYY | 14 | 89.7(97.4) | 0 | 2 | 0.0% | 76 | 88 | FF/ST |
| 2024-09-12 | NYY | 2 | 81.6(81.7) | 0 | 0 | 0.0% | - | - | - |
| 2024-09-10 | BAL | 24 | 90.3(97.3) | 2 | 2 | 8.3% | 77 | 88 | CH/FC |
| 2024-09-08 | CWS | 25 | 87.5(98.2) | 1 | 0 | 12.0% | 77 | 94 | CH/ST |
| 2024-09-06 | CWS | 17 | 87.9(97.5) | 0 | 0 | 11.8% | 79 | 85 | FF/ST |
| 2024-09-04 | NYM | 13 | 87.4(98.0) | 1 | 0 | 15.4% | 79 | 88 | FF/ST |
| 2024-09-01 | DET | 14 | 87.0(97.1) | 1 | 0 | 28.6% | 78 | 100 | CH/ST |
| 2024-08-26 | TOR | 49 | 89.5(97.9) | 4 | 2 | 10.2% | 75 | 85 | FF/ST |
| 2024-08-24 | AZ | 13 | 87.3(98.2) | 1 | 0 | 23.1% | 79 | 100 | CH/ST |
| 2024-08-21 | HOU | 5 | 94.2(97.0) | 0 | 0 | 0.0% | - | - | - |
| 2024-08-20 | HOU | 8 | 96.1(98.5) | 0 | 0 | 12.5% | - | - | - |
| 2024-08-16 | BAL | 6 | 86.2(96.3) | 0 | 0 | 0.0% | - | - | - |
| 2024-08-14 | TEX | 17 | 92.2(98.3) | 1 | 0 | 11.8% | 76 | 59 | CH/FF |
| 2024-08-12 | TEX | 16 | 93.2(98.3) | 1 | 1 | 0.0% | 74 | 48 | FC/FF |
| 2024-08-10 | HOU | 17 | 92.5(98.5) | 1 | 0 | 5.9% | 73 | 54 | FC/FF |
| 2024-08-09 | HOU | 15 | 86.8(97.6) | 0 | 0 | 0.0% | 77 | 55 | FC/ST |
| 2024-08-06 | KC | 10 | 86.0(95.9) | 2 | 0 | 20.0% | 78 | - | - |
| 2024-08-04 | TEX | 23 | 88.0(96.7) | 1 | 0 | 21.7% | 80 | 94 | FF/ST |
| 2024-07-31 | SEA | 15 | 92.8(98.6) | 1 | 1 | 6.7% | 78 | 50 | FC/FF |
| 2024-07-30 | SEA | 16 | 86.5(98.0) | 0 | 2 | 6.3% | 74 | 100 | CH/ST |
| 2024-07-27 | NYY | 7 | 93.2(98.9) | 0 | 0 | 14.3% | - | - | - |
| 2024-07-26 | NYY | 16 | 86.8(97.4) | 0 | 0 | 0.0% | 75 | 99 | CH/ST |
| 2024-07-22 | COL | 26 | 88.0(97.8) | 3 | 0 | 30.8% | 78 | 76 | CH/ST |
| 2024-07-19 | LAD | 30 | 87.9(97.3) | 2 | 2 | 13.3% | 77 | 79 | CH/ST |
| 2024-07-13 | KC | 24 | 89.1(97.5) | 2 | 0 | 8.3% | 73 | 89 | FF/ST |
| 2024-07-09 | ATH | 7 | 85.3(89.8) | 1 | 0 | 14.3% | - | - | - |
| 2024-07-04 | MIA | 34 | 88.0(97.3) | 3 | 0 | 11.8% | 73 | 94 | CH/ST |
| 2024-07-02 | MIA | 18 | 88.4(96.3) | 1 | 0 | 16.7% | 76 | 97 | CH/ST |
| 2024-06-29 | SD | 31 | 89.2(97.8) | 2 | 0 | 6.5% | 71 | 94 | CH/ST |
| 2024-06-23 | CIN | 33 | 87.6(96.8) | 3 | 0 | 18.2% | 77 | 84 | CH/ST |
| 2024-06-22 | CIN | 6 | 89.9(94.2) | 0 | 0 | 0.0% | - | - | - |
| 2024-06-18 | TOR | 18 | 88.5(98.0) | 1 | 0 | 16.7% | 77 | 100 | FF/ST |
| 2024-06-16 | NYY | 13 | 88.3(96.0) | 2 | 0 | 23.1% | 82 | 61 | FC/ST |
| 2024-06-14 | NYY | 21 | 86.8(97.1) | 3 | 0 | 14.3% | 74 | 95 | CH/ST |
| 2024-06-12 | PHI | 16 | 88.9(96.8) | 2 | 1 | 18.8% | 76 | 100 | FF/ST |
| 2024-06-09 | CWS | 32 | 88.8(96.5) | 3 | 2 | 12.5% | 80 | 92 | FF/ST |
| 2024-06-08 | CWS | 5 | 84.1(88.6) | 0 | 0 | 20.0% | - | - | - |
| 2024-06-05 | ATL | 12 | 86.6(96.6) | 2 | 0 | 16.7% | 78 | 100 | CH/ST |
| 2024-05-25 | MIL | 42 | 85.5(95.9) | 2 | 0 | 9.5% | 75 | 93 | CH/ST |
| 2024-05-22 | TB | 33 | 89.1(96.4) | 1 | 1 | 6.1% | 78 | 90 | FF/ST |
| 2024-05-18 | STL | 18 | 90.9(97.6) | 0 | 0 | 5.6% | 77 | 77 | FF/ST |
| 2024-05-16 | TB | 29 | 89.0(96.9) | 1 | 4 | 6.9% | 81 | 90 | FF/ST |
| 2024-05-14 | TB | 24 | 85.6(96.7) | 2 | 0 | 12.5% | 75 | 100 | CH/ST |
| 2024-05-12 | WSH | 24 | 90.3(96.6) | 0 | 2 | 12.5% | 76 | 100 | FF/ST |
| 2024-05-05 | MIN | 34 | 91.7(97.8) | 2 | 2 | 11.8% | 75 | 87 | FF/ST |
| 2024-05-02 | SF | 23 | 87.3(96.6) | 0 | 0 | 0.0% | 75 | 82 | CH/ST |
| 2024-04-30 | SF | 20 | 88.8(96.5) | 2 | 0 | 10.0% | 68 | 100 | FF/ST |
| 2024-04-26 | CHC | 26 | 88.8(96.6) | 1 | 0 | 7.7% | 81 | 95 | CH/ST |
| 2024-04-24 | CLE | 28 | 90.6(97.3) | 3 | 0 | 25.0% | 76 | 71 | CH/FF |
| 2023-09-28 | BAL | 23 | 88.7(96.9) | 0 | 2 | 8.7% | 80 | 72 | CH/SL |
| 2023-09-26 | TB | 13 | 90.7(95.4) | 0 | 0 | 0.0% | 76 | 52 | CH/FF |
| 2023-04-12 | TB | 23 | 88.6(95.5) | 1 | 1 | 13.0% | 77 | 74 | FC/FF |
| 2023-04-08 | DET | 32 | 89.1(96.1) | 1 | 1 | 6.3% | 76 | 84 | CH/SL |
| 2023-04-05 | PIT | 22 | 88.1(95.2) | 0 | 1 | 4.5% | 75 | 75 | CH/SL |
| 2023-04-03 | PIT | 30 | 86.9(95.8) | 2 | 1 | 16.7% | 78 | 76 | CH/SL |
| 2023-04-01 | BAL | 16 | 88.6(96.4) | 0 | 0 | 0.0% | 60 | 45 | CH/FF |
| 2023-03-30 | BAL | 22 | 89.6(95.0) | 2 | 2 | 4.5% | 74 | 78 | FF/SL |
| 2022-10-01 | TOR | 26 | 86.8(95.5) | 1 | 0 | 15.4% | 78 | 71 | CH/SL |
| 2022-09-29 | BAL | 19 | 89.1(95.3) | 1 | 0 | 15.8% | 77 | 72 | FF/SL |
| 2022-09-27 | BAL | 9 | 86.5(95.2) | 0 | 0 | 0.0% | - | - | - |
| 2022-09-26 | BAL | 21 | 90.6(94.3) | 1 | 0 | 4.8% | 77 | 79 | FF/SL |
| 2022-09-23 | NYY | 11 | 89.9(94.2) | 1 | 0 | 27.3% | 75 | 71 | CH/FF |
| 2022-09-20 | CIN | 5 | 91.1(93.9) | 0 | 0 | 0.0% | - | - | - |
| 2022-09-14 | NYY | 24 | 88.3(97.3) | 1 | 1 | 8.3% | 77 | 67 | CH/SL |
| 2022-09-09 | BAL | 26 | 88.7(96.3) | 1 | 1 | 3.8% | 82 | 40 | CH/FF |
| 2022-09-07 | TB | 7 | 89.7(95.4) | 0 | 0 | 0.0% | - | - | - |
| 2022-09-05 | TB | 18 | 86.1(95.6) | 1 | 0 | 5.6% | 77 | 85 | CH/SL |
| 2022-09-01 | TEX | 29 | 88.2(96.7) | 1 | 2 | 3.4% | 80 | 64 | CH/SL |
| 2022-08-30 | MIN | 9 | 88.7(96.4) | 1 | 0 | 11.1% | - | - | - |
| 2022-08-29 | MIN | 18 | 88.6(95.9) | 2 | 0 | 0.0% | 78 | 42 | CH/FF |