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Kumar Rocker

2026
Rangers· RHP · throws R· 148.0 IP· 4.38 ERA· 1.41 WHIP· 645 batters faced
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Grade

His grade shows how good he has been, and at what.
C+better than 53% of qualified pitchers at limiting bases
StarterPower Arm

Misses bats in bunches; lives with the walks.

Rocker sits right around league average

The simulator expects him to allow 0.451 bases per batter faced, better than 53% of qualified pitchers. His weakest skill is limiting hard contact (28th percentile).

His grade rests on 645 batters faced, with data through 2026-09-27.

How to read this chart
Each spoke is a skill estimate adjusted for sample size, not a raw season stat, and farther out is better. A ↓ marks a stat where a lower number is better, and its spoke is flipped so farther out still means better. The middle ring marks the league median and the outer ring the league best. Percentiles compare him with 517 qualified pitchers, those with 100+ batters faced, starters and relievers together.

Plays like…

Each of these pitchers shares his archetype and sits closest to him in xEB/PA. Pick one to see him side by side with Kumar Rocker.

Tyler ZuberMarlinsCole WinnRangersKyle LeahyCardinalsChase ShugartPhillies

Pitcher type

This map shows what kind of pitcher he is, next to the league.

Pitcher type

He lands in the “Hit hard, few strikeouts” corner of the map.

League best:K% − BB% Jacob Misiorowski (26.8%)Hard-hit% allowed Blake Snell (29.0%)

How to read this chart
Two skills separate pitching styles: strikeout rate minus walk rate, where higher is better, and hard-hit rate allowed, where lower is better. The hard-hit axis is flipped, so the best corner is the top right. Each dot is a pitcher with 80+ batters faced this season, sized by batters faced. The dashed lines are the league median on each skill, and the league best on each is named above the chart. Click any dot to open that pitcher's page.
 Kumar RockerLeague medianPercentile
Bases per ball in play(lower = better).513.527—
Walk rate(lower = better)10%9%45th
Strikeout rate(higher = better)21%22%40th

A higher percentile is better, and the 99th is the top of the league.

Arsenal

These cards show what he throws and what each pitch does.

Kumar Rocker mixes his slider (38%) and sinker (30%). His best pitch has been the slider, saving 1.4 bases per 100 thrown against league average, with a 43% whiff rate against a league median of 33%.

Pitch mix & swing-and-miss

+91 bases better than a replacement arm this season

He allowed about 287 estimated bases, against a replacement arm's 378 over the same batters faced.

Replacement level is per-batter and can't be split by pitch type, so the bars below use league average.

All pitches

He saved 4.2 bases against league average across 2,487 pitches, or 0.2 per 100 pitches.

Slider
38%
83.1 mph · RHP median 86.9
43% whiffs · Lg median 33%
saved 1.4 per 10013.1 total
Sinker
30%
94.3 mph · RHP median 94.7
9% whiffs · Lg median 13%
eveneven
Four-Seam Fastball
15%
94.5 mph · RHP median 95.1
23% whiffs · Lg median 21%
eveneven
Cutter
14%
90.2 mph · RHP median 90.1
21% whiffs · Lg median 22%
cost 1.4 per 1005.0 total
Changeup
4%
88.6 mph · RHP median 87.1
24% whiffs · Lg median 30%
cost 4.0 per 1003.8 total

He rarely throws his splitter (0% of his pitches).

How to read this chart
Each row is a pitch he throws at least 3% of the time, from pitch tracking in the regular season. The bar is how often he throws it, then its average velocity and its whiff rate, the share of swings that miss. Beside the velocity and the whiff rate is the median for that pitch, among pitchers of his hand for velocity and across the league for whiffs. More whiffs are better for a pitcher, while usage and velocity describe how he pitches. The Bases vs average bars score each pitch against a league-average pitch in the same count, and a bar to the left (saved) is better.

Mix by batter side

Slider
38% vs LHH · RHP median 20%
38% vs RHH · RHP median 30%
Sinker
22% vs LHH · RHP median 16%
40% vs RHH · RHP median 33%
Four-Seam Fastball
19% vs LHH · RHP median 40%
8% vs RHH · RHP median 33%
Cutter
14% vs LHH · RHP median 20%
14% vs RHH · RHP median 19%
How to read this chart
Each row shows how often he throws a pitch to left-handed hitters (LHH) and right-handed hitters (RHH), next to the median for pitchers of his hand (RHP median). Medians come from right-handed pitchers who throw that pitch at least 3% of the time. Between 156 and 384 of them qualify, depending on the pitch. A mix is a plan, so a higher or lower share is neither better nor worse. Overall results by batter side are under Platoon splits.

Kumar Rocker's pitch movement, 2026

His Cutter and Changeup have moved 2+ inches from their early-season shapes.

The verdict above compares each pitch with his own early-season outings in 2026, not with other pitchers, after taking out the league-wide drift in break.

Kumar Rocker's pitch movement, 2026061218-6061218in← glove sidearm side →more risemore drop
SliderSL
Rise −4.2 in
−6.0 vs Lg median
Break −0.5 in
+3.2 vs Lg median
Vs. early season steady
SinkerSI
Rise 7.3 in
−1.0 vs Lg median
Break 16.8 in
+1.6 vs Lg median
Vs. early season steady
Four-Seam FastballFF
Rise 12.6 in
−3.1 vs Lg median
Break 11.0 in
+3.3 vs Lg median
Vs. early season steady
CutterFC
Rise 7.9 in
+0.2 vs Lg median
Break −0.7 in
+1.4 vs Lg median
Vs. early season changed
ChangeupCH
Rise 4.2 in
+0.1 vs Lg median
Break 14.7 in
+0.5 vs Lg median
Vs. early season changed
Early season → nowLg medianNormal wobble around the dot
How to read this chart
Each dot is a pitch's current break in inches, averaged over his latest outings. Higher is more rise and further right is more arm-side break, and neither is better or worse. The faint trail runs from his early-season outings to the dot, and the soft halo shows how far normal noise can move it. League median is the small hollow ring, and a pitch marked * has none because too few pitchers throw it. The “changed” verdict removes a league-wide drift that the trail still shows, so a long trail can read as steady. The by-appearance chart below has the exact dates. More on the About page

By appearance

These charts follow his velocity, movement and mix from outing to outing.

These charts follow his velocity, movement and pitch mix one outing at a time, and each pitch keeps the same color in every chart. The velocity and movement charts also shade the middle of the league for scale.

Platoon splits

This section splits his results against lefties and righties.

Platoon splits (EB/PA allowed)

He handles righty bats better than lefty bats, by 0.045 EB/PA allowed.

50% probable range: +0.037 to +0.053

vs LHB368 PA0.474

vs LHB: shrunk estimate 0.474 EB/PA, 50% probable range 0.459 to 0.490, based on 368 plate appearances. Raw (unshrunk) rate: 0.508 EB/PA. League median vs LHB: 0.451 EB/PA.

His raw rate vs LHB (0.508) is off this scale. Small samples can push a raw rate this far, which is why the dot, the shrunk estimate, is the number to trust.

vs RHB279 PA0.429

vs RHB: shrunk estimate 0.429 EB/PA, 50% probable range 0.413 to 0.444, based on 279 plate appearances. Raw (unshrunk) rate: 0.373 EB/PA. League median vs RHB: 0.435 EB/PA.

His raw rate vs RHB (0.373) is off this scale. Small samples can push a raw rate this far, which is why the dot, the shrunk estimate, is the number to trust.

0.4040.4270.4510.4750.499
← betterworse →
Below league medianAbove50% probable rangeHis raw rateMiddle half of the league

His split is about typical for a righty arm (median 0.042). Against lefty bats he allows more than the league median, which is a real platoon weakness.

How to read this chart
  • Each dot is his estimate against that side, with its 50% probable range as the bar. These are bases allowed, so lower is better.
  • The diamond is his raw rate, which small samples make noisy, so the simulator pulls the dot toward a more trustworthy value.
  • The dashed tick is the league median, and the shaded strip is the middle half of pitchers with 100 or more batters faced.
  • The two splits average back to his modeled overall EB/PA allowed, not the xEB/PA headline.
  • Tap or hover a mark for its number. LHB and RHB are left- and right-handed batters. More on the About page

Contact allowed

These cards show what hitters do when they make contact.

Batters go to the pull side off him most often, and that's also where they do the most damage.

Pull side and opposite field depend on which side each batter hits from, so this pools every hitter he faced.

Batted balls allowed

Every ball hit off Kumar Rocker this season is drawn where it landed.
hit · out
EBlowhigh
vs Trevor LarnachHome run
109 mph · 31° · worth 3.9 bases
06/16 vs Twins
vs Pete AlonsoHome run
104 mph · 29° · worth 3.9 bases
08/09 vs Orioles
vs Riley GreeneHome run
111 mph · 36° · worth 3.9 bases
07/05 vs Tigers
vs Dillon DinglerHome run
108 mph · 30° · worth 3.8 bases
05/02 vs Tigers
vs Yordan AlvarezHome run
113 mph · 28° · worth 3.8 bases
07/11 vs Astros

Luck check

5 outs behind him came on balls the simulator values at 1.5 bases or more.

vs Daylen LileOutLucky out
106 mph · 26° · worth 3.3 bases
08/19 vs Nationals
How to read this chart
Dot color is estimated bases (EB), what the contact was worth no matter what the defense did with it. Darker means more bases, so a dark hollow ring in the outfield is a crushed ball his defense ran down. Tap or hover a dot or a row to link the two, and use the ▶ links to watch a play on Baseball Savant.

Deserved vs. actual

Batters have been credited with about 19 more bases than their contact off Kumar Rocker deserved, so his results have been unlucky so far.

Deserved by the contact he allowed226
Actually credited to batters245

Both bars count 441 balls in play, with walks and strikeouts left out.

How to read this chart
Every ball in play is worth the bases its exit velocity, launch angle and direction usually produce. If batters were credited with more than that, his results have been unlucky, and fewer means lucky. BABIP against is the batting average on balls in play he allows, next to the league median.

ERA 4.38 · WHIP 1.41 · BABIP against 0.302 (Lg median 0.286)

Times through the order

These charts show what happens as hitters see him a second and third time.

Best games

These are his biggest outings this season.

Best games

These are his best outings this season, ranked by bases saved against a replacement arm.

Multi-season trends · Kumar Rocker

Compared with last season, his HR allowed% is down, his BB% is up, his Barrel% against is down, his Hard-hit% against is down, his GB% against is down, his FB% against is up and his Pull% against is up.

Actual rates show what happened on the field, season by season.