John Brontsema
| Year | Age | Lvl / Team | PA | AVG/OBP/SLG | HR | SB | wRC+ | WAR | MLE AVG/OBP/SLG |
|---|---|---|---|---|---|---|---|---|---|
| 2016 | 21 | ROKAZL Royals | 195 | .343/.401/.406 | 0 | 9 | 63 | — | .256/.302/.300 |
| 2017 | 22 | A+/A2 orgs | 258 | .296/.384/.435 | 5 | 6 | 83 | — | .252/.321/.361 |
| 2018 | 23 | AA/A+2 orgs | 139 | .231/.326/.339 | 2 | 5 | 48 | — | .198/.268/.293 |
Career Stats + Projections
Methodology▸ how these numbers are built
All seasons translated to park-neutral MLB-equivalent (MLE) and combined per year. 2027 = full-season projection (no games played yet). 2028+ via Advanced Marcel + aging curve.
| Year | Age | Lvl | Team | MLB% | PA | AB | H | 2B | 3B | HR | BB | SO | HBP | SB | CS | AVG | OBP | SLG | OPS | ISO | BABIP | K% | BB% | wOBA | wRC+ | BAT | RUN | FLD | POS | REP | WAR |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ▸ Career — actual stats, one row per stint (as recorded, no adjustments) | |||||||||||||||||||||||||||||||
| 2016 | 21 | ROK | AZL Royals | — | 195 | 175 | 60 | 9 | 1 | 0 | 13 | 30 | 4 | 9 | 4 | 343 | 401 | 406 | 807 | 63 | 405 | 15 | 7 | 361 | 63 | — | — | — | — | — | — |
| 2017 | 22 | A+ | Wilmington Blue Rocks | — | 68 | 62 | 14 | 2 | 0 | 1 | 5 | 19 | 0 | 0 | 1 | 226 | 284 | 306 | 590 | 81 | 310 | 28 | 7 | 266 | 29 | — | — | — | — | — | — |
| 2017 | 22 | A | Lexington Legends | — | 190 | 161 | 52 | 12 | 1 | 4 | 17 | 41 | 10 | 6 | 2 | 323 | 420 | 484 | 905 | 161 | 407 | 22 | 9 | 401 | 103 | — | — | — | — | — | — |
| 2018 | 23 | AA | Northwest Arkansas Naturals | — | 123 | 109 | 25 | 5 | 1 | 2 | 8 | 31 | 5 | 5 | 1 | 229 | 311 | 349 | 660 | 119 | 299 | 25 | 7 | 299 | 47 | — | — | — | — | — | — |
| 2018 | 23 | A+ | Wilmington Blue Rocks | — | 16 | 12 | 3 | 0 | 0 | 0 | 4 | 4 | 0 | 0 | 1 | 250 | 438 | 250 | 688 | 375 | 25 | 25 | 344 | 56 | — | — | — | — | — | — | |
| ▸ Career — adjusted (every ACTUAL line translated to park/league-neutral MLB equivalents) | |||||||||||||||||||||||||||||||
| 2016 | 21 | ROK MLE | AZL Royals | — | 195 | 180 | 46 | 6 | 1 | 0 | 8 | 43 | 4 | 9 | 4 | 256 | 302 | 300 | 602 | 44 | 316 | 22 | 4 | 262 | 63 | — | — | — | — | — | — |
| 2017 | 22 | A+ MLE | Wilmington Blue Rocks | — | 68 | 64 | 12 | 2 | 0 | 1 | 3 | 27 | 0 | 0 | 1 | 188 | 224 | 266 | 490 | 78 | 295 | 40 | 4 | 211 | 29 | — | — | — | — | — | — |
| 2017 | 22 | A MLE | Lexington Legends | — | 190 | 167 | 46 | 9 | 1 | 3 | 11 | 55 | 10 | 6 | 2 | 275 | 356 | 395 | 752 | 120 | 371 | 29 | 6 | 321 | 103 | — | — | — | — | — | — |
| 2018 | 23 | AA MLE | Northwest Arkansas Naturals | — | 123 | 112 | 22 | 4 | 1 | 2 | 5 | 39 | 5 | 5 | 1 | 196 | 262 | 304 | 566 | 107 | 260 | 32 | 4 | 237 | 47 | — | — | — | — | — | — |
| 2018 | 23 | A+ MLE | Wilmington Blue Rocks | — | 16 | 14 | 3 | 0 | 0 | 0 | 2 | 6 | 0 | 0 | 1 | 214 | 312 | 214 | 527 | 341 | 38 | 12 | 251 | 56 | — | — | — | — | — | — | |
| 2016 | 21 | ROK MLE | AZL Royals | — | 195 | 180 | 46 | 6 | 1 | 0 | 8 | 43 | 4 | 9 | 4 | 256 | 302 | 300 | 602 | 44 | 329 | 22 | 4 | 262 | 63 | — | — | — | — | — | — |
| 2016 | 21 | ROK RAW | AZL Royals | — | 195 | 175 | 60 | 9 | 1 | 0 | 13 | 30 | 4 | 9 | 4 | 343 | 401 | 406 | 807 | 63 | 405 | 15 | 7 | 361 | 63 | — | — | — | — | — | — |
| 2017 | 22 | A MLE | 2 teams | — | 258 | 231 | 58 | 11 | 1 | 4 | 14 | 82 | 10 | 6 | 3 | 251 | 322 | 359 | 681 | 108 | 367 | 32 | 5 | 292 | 84 | — | — | — | — | — | — |
| 2017 | 22 | A RAW | 2 teams | — | 258 | 223 | 66 | 14 | 1 | 5 | 22 | 60 | 10 | 6 | 3 | 296 | 384 | 435 | 819 | 139 | 381 | 23 | 9 | 366 | 84 | — | — | — | — | — | — |
| 2018 | 23 | AA MLE | 2 teams | — | 139 | 125 | 24 | 4 | 1 | 2 | 8 | 44 | 5 | 5 | 2 | 192 | 268 | 288 | 556 | 96 | 275 | 32 | 6 | 239 | 48 | — | — | — | — | — | — |
| 2018 | 23 | AA RAW | 2 teams | — | 139 | 121 | 28 | 5 | 1 | 2 | 12 | 35 | 5 | 5 | 2 | 231 | 326 | 339 | 665 | 107 | 306 | 25 | 9 | 305 | 48 | — | — | — | — | — | — |
| 2016 | 21 | ROK MLE | AZL Royals | — | 195 | 181 | 46 | 6 | 1 | 0 | 8 | 43 | 4 | 9 | 4 | 254 | 302 | 298 | 600 | 44 | 316 | 22 | 4 | 262 | 63 | — | — | — | — | — | — |
| 2017 | 22 | A MLE | 2 teams | — | 258 | 232 | 58 | 11 | 1 | 4 | 14 | 82 | 10 | 6 | 3 | 250 | 322 | 358 | 679 | 108 | 351 | 32 | 5 | 292 | 84 | — | — | — | — | — | — |
| 2018 | 23 | AA MLE | 2 teams | — | 139 | 125 | 24 | 4 | 1 | 2 | 8 | 44 | 5 | 5 | 2 | 192 | 268 | 288 | 556 | 96 | 269 | 32 | 6 | 239 | 48 | — | — | — | — | — | — |
| ▸ Career Totals | |||||||||||||||||||||||||||||||
| Career | — | MLE | — | 592 | 536 | 128 | 21 | 3 | 6 | 30 | 169 | 19 | 20 | 9 | 239 | 303 | 323 | 625 | 84 | 332 | 29 | 5 | 270 | 69 | -22 | +0 | +0 | +2 | +13 | -0.7 | |
| / 162G | — | MLE | — | 650 | 589 | 141 | 23 | 3 | 7 | 33 | 186 | 21 | 22 | 10 | 239 | 304 | 324 | 628 | 85 | 333 | 29 | 5 | 270 | 69 | -24 | +0 | +0 | +2 | +14 | -0.8 | |
How the minor-league lines were translated
One row per minor-league stint. Open a row to see each step: the raw rate, the park adjustment, the league/level factor, the age adjustment (hitters) and the resulting MLE rate. Factors are the same ones listed on the MLE Factors page.
2018 AANorthwest Arkansas Naturals · 123 PAwOBA .294 → .237 (−57)K% 25.2% → 31.4%
| Component | Raw | Park ÷ | Level factor × | GB/FB × | Age × | = MLE |
|---|---|---|---|---|---|---|
| K% /PA | 25.20% | ÷0.979 | ×1.220 | — | — | 31.39% |
| BB% (unintentional) /PA | 6.50% | ÷1.049 | ×0.700 | — | ×1.012 | 4.39% |
| HBP% /PA | 4.07% | — | ×0.870 | — | ×1.012 | 3.58% |
| Singles /BIP | 21.79% | ÷1.046 | ×0.920 | ×1.010 | ×1.012 | 19.59% |
| Doubles /BIP | 6.41% | ÷1.113 | ×0.840 | ×1.010 | ×1.012 | 4.95% |
| Triples /BIP | 1.28% | ÷0.956 | ×0.940 | ×1.010 | ×1.012 | 1.29% |
| Home runs /BIP | 2.56% | ÷1.008 | ×0.800 | — | ×1.012 | 2.06% |
Factors used: league row TL. Park (home-season share, regressed): HR 102, 1B 109, 2B 123, 3B 91, K 96, BB 110 — applied at half strength. Age: age 24 vs a level average of 24.8 → +1.2% on BB/HBP/hit rates (0.8 yr younger than average). Ground-ball/fly-ball mix moves 1B/2B/3B by ×1.010.
Result: wOBA .294 → .237; ISO .119 → .094; BABIP .299 → .260. Both wOBAs use the same linear weights, so the change is the translation alone. The MLE line is not regressed to the mean — regression happens later, when seasons are blended into a projection (how).
2018 A+Wilmington Blue Rocks · 16 PAwOBA .338 → .251 (−87)K% 25.0% → 35.1%
| Component | Raw | Park ÷ | Level factor × | GB/FB × | Age × | = MLE |
|---|---|---|---|---|---|---|
| K% /PA | 25.00% | ÷1.010 | ×1.420 | — | — | 35.15% |
| BB% (unintentional) /PA | 25.00% | ÷1.077 | ×0.630 | — | ×0.988 | 14.46% |
| HBP% /PA | 0.00% | — | ×0.860 | — | ×0.988 | 0.00% |
| Singles /BIP | 37.50% | ÷1.021 | ×0.940 | — | ×0.988 | 34.11% |
| Doubles /BIP | 0.00% | ÷1.005 | ×0.830 | — | ×0.988 | 0.00% |
| Triples /BIP | 0.00% | ÷0.965 | ×0.800 | — | ×0.988 | 0.00% |
| Home runs /BIP | 0.00% | ÷0.773 | ×0.900 | — | ×0.988 | 0.00% |
Factors used: league row CAR. Park (home-season share, regressed): HR 55, 1B 104, 2B 101, 3B 93, K 102, BB 115 — applied at half strength. Age: age 24 vs a level average of 22.8 → −1.2% on BB/HBP/hit rates (1.2 yr older than average).
Result: wOBA .338 → .251; ISO .000 → .000; BABIP .375 → .341. Both wOBAs use the same linear weights, so the change is the translation alone. The MLE line is not regressed to the mean — regression happens later, when seasons are blended into a projection (how).
2017 ALexington Legends · 190 PAwOBA .395 → .321 (−74)K% 21.6% → 29.2%
| Component | Raw | Park ÷ | Level factor × | GB/FB × | Age × | = MLE |
|---|---|---|---|---|---|---|
| K% /PA | 21.58% | ÷0.991 | ×1.340 | — | — | 29.18% |
| BB% (unintentional) /PA | 8.95% | ÷1.053 | ×0.660 | — | ×0.990 | 5.55% |
| HBP% /PA | 5.26% | — | ×0.770 | — | ×0.990 | 4.01% |
| Singles /BIP | 29.17% | ÷0.936 | ×0.920 | ×0.986 | ×0.990 | 27.99% |
| Doubles /BIP | 10.00% | ÷0.982 | ×0.820 | ×0.986 | ×0.990 | 8.15% |
| Triples /BIP | 0.83% | ÷1.125 | ×0.940 | ×0.986 | ×0.990 | 0.68% |
| Home runs /BIP | 3.33% | ÷1.062 | ×0.820 | — | ×0.990 | 2.55% |
Factors used: league row SAL. Park (home-season share, regressed): HR 112, 1B 87, 2B 96, 3B 125, K 98, BB 111 — applied at half strength. Age: age 23 vs a level average of 22.0 → −1.0% on BB/HBP/hit rates (1.0 yr older than average). Ground-ball/fly-ball mix moves 1B/2B/3B by ×0.986.
Result: wOBA .395 → .321; ISO .161 → .124; BABIP .407 → .371. Both wOBAs use the same linear weights, so the change is the translation alone. The MLE line is not regressed to the mean — regression happens later, when seasons are blended into a projection (how).
2017 A+Wilmington Blue Rocks · 68 PAwOBA .259 → .211 (−49)K% 27.9% → 39.6%
| Component | Raw | Park ÷ | Level factor × | GB/FB × | Age × | = MLE |
|---|---|---|---|---|---|---|
| K% /PA | 27.94% | ÷1.002 | ×1.420 | — | — | 39.58% |
| BB% (unintentional) /PA | 7.35% | ÷0.979 | ×0.630 | — | ×0.998 | 4.72% |
| HBP% /PA | 0.00% | — | ×0.860 | — | ×0.998 | 0.00% |
| Singles /BIP | 25.58% | ÷1.017 | ×0.940 | ×1.043 | ×0.998 | 24.61% |
| Doubles /BIP | 4.65% | ÷0.978 | ×0.830 | ×1.043 | ×0.998 | 4.11% |
| Triples /BIP | 0.00% | ÷1.025 | ×0.800 | ×1.043 | ×0.998 | 0.00% |
| Home runs /BIP | 2.33% | ÷0.810 | ×0.900 | — | ×0.998 | 2.58% |
Factors used: league row CAR. Park (home-season share, regressed): HR 62, 1B 103, 2B 96, 3B 105, K 100, BB 96 — applied at half strength. Age: age 23 vs a level average of 22.8 → −0.2% on BB/HBP/hit rates (0.2 yr older than average). Ground-ball/fly-ball mix moves 1B/2B/3B by ×1.043.
Result: wOBA .259 → .211; ISO .081 → .072; BABIP .310 → .295. Both wOBAs use the same linear weights, so the change is the translation alone. The MLE line is not regressed to the mean — regression happens later, when seasons are blended into a projection (how).
2016 ROKAZL Royals · 195 PAwOBA .357 → .262 (−96)K% 15.4% → 22.2%
| Component | Raw | Park ÷ | Level factor × | GB/FB × | Age × | = MLE |
|---|---|---|---|---|---|---|
| K% /PA | 15.38% | ÷1.000 | ×1.440 | — | — | 22.15% |
| BB% (unintentional) /PA | 6.67% | ÷1.000 | ×0.620 | — | ×0.975 | 4.03% |
| HBP% /PA | 2.05% | — | ×0.720 | — | ×0.975 | 1.44% |
| Singles /BIP | 34.48% | ÷1.000 | ×0.820 | ×0.995 | ×0.975 | 27.44% |
| Doubles /BIP | 6.21% | ÷1.000 | ×0.720 | ×0.995 | ×0.975 | 4.34% |
| Triples /BIP | 0.69% | ÷1.000 | ×0.720 | ×0.995 | ×0.975 | 0.48% |
| Home runs /BIP | 0.00% | ÷1.000 | ×0.780 | — | ×0.975 | 0.00% |
Factors used: level-wide ROK factors (no league-specific row for this league/era). Park (home-season share, regressed): no park row on file (treated as neutral) — applied at half strength. Age: age 22 vs a level average of 19.5 → −2.5% on BB/HBP/hit rates (2.5 yr older than average). Ground-ball/fly-ball mix moves 1B/2B/3B by ×0.995.
Result: wOBA .357 → .262; ISO .063 → .043; BABIP .405 → .316. Both wOBAs use the same linear weights, so the change is the translation alone. The MLE line is not regressed to the mean — regression happens later, when seasons are blended into a projection (how).