Skip to main content
MLB Deserve-to-Win
← All pitchers·All hitters

Robby Ahlstrom

2026
Rangers· LHP · throws L· 37.0 IP· 6.08 ERA· 1.43 WHIP· 164 batters faced
Compare

Grade

His grade shows how good he has been, and at what.
Dbetter than 32% of qualified pitchers at limiting bases
RelieverStill Searching

Below league average across the board.

Ahlstrom has been below average at limiting bases

The simulator expects him to allow 0.464 bases per batter faced, better than 32% of qualified pitchers. His best skill is limiting hard contact (93rd percentile). His weakest skill is limiting home runs (11th percentile). Short relief outings push strikeout rates up a little, so read his K% spoke with that in mind.

His grade rests on 164 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 Robby Ahlstrom.

George SorianoCardinalsRyne StanekCardinalsBlake TreinenDodgersTyler KinleyTigers

Pitcher type

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

Pitcher type

He lands in the “Limits hard contact, pitches to contact” 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.
 Robby AhlstromLeague medianPercentile
Bases per ball in play(lower = better).529.527—
Walk rate(lower = better)9%9%45th
Strikeout rate(higher = better)21%22%38th

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.

Robby Ahlstrom mixes his four-seam fastball (33%) and slider (26%). His best pitch has been the sinker, saving 2.7 bases per 100 thrown against league average.

Pitch mix & swing-and-miss

+11 bases better than a replacement arm this season

He allowed about 74 estimated bases, against a replacement arm's 86 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 cost 0.2 bases against league average across 624 pitches, or 0.0 per 100 pitches.

Four-Seam Fastball
33%
94.4 mph · LHP median 93.5
30% whiffs · Lg median 21%
cost 1.3 per 1002.8 total
Slider
26%
85.9 mph · LHP median 85.6
36% whiffs · Lg median 33%
saved 2.3 per 1003.9 total
Sinker
22%
94.4 mph · LHP median 92.9
14% whiffs · Lg median 13%
saved 2.7 per 1003.9 total
Changeup
16%
86.7 mph · LHP median 85.1
21% whiffs · Lg median 30%
cost 5.1 per 1005.2 total
Curveball
not charted
4%
81.0 mph · LHP median 79.9
—
—

His curveball isn't in the charts below, because only 24 of them were tracked with velocity and movement data this season.

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

Compared with the league, his slider tilts 26 points more toward lefties.

Four-Seam Fastball
22% vs LHH · LHP median 34%
41% vs RHH · LHP median 41%
Slider
48% vs LHH · LHP median 33%
8% vs RHH · LHP median 18%
Sinker
29% vs LHH · LHP median 38%
17% vs RHH · LHP median 22%
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 (LHP median). Medians come from left-handed pitchers who throw that pitch at least 3% of the time. Between 103 and 149 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.

Robby Ahlstrom's pitch movement, 2026

His Four-Seam Fastball 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.

Robby Ahlstrom's pitch movement, 20260612061218in← glove sidearm side →more risemore drop
Four-Seam FastballFF
Rise 17.5 in
+1.8 vs Lg median
Break 6.5 in
−1.2 vs Lg median
Vs. early season changed
SliderSL
Rise 4.4 in
+2.6 vs Lg median
Break −2.5 in
+1.2 vs Lg median
Vs. early season steady
SinkerSI
Rise 12.8 in
+4.5 vs Lg median
Break 14.5 in
−0.7 vs Lg median
Vs. early season steady
ChangeupCH
Rise 5.6 in
+1.5 vs Lg median
Break 12.4 in
−1.8 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. His curveball isn't in these charts, because only 24 of them were tracked with velocity and movement data this season.

Platoon splits

This section splits his results against lefties and righties.

Platoon splits (EB/PA allowed)

He handles lefty bats better than righty bats, by 0.039 EB/PA allowed.

50% probable range: +0.031 to +0.048

vs LHB79 PA0.432

vs LHB: shrunk estimate 0.432 EB/PA, 50% probable range 0.410 to 0.453, based on 79 plate appearances. Raw (unshrunk) rate: 0.374 EB/PA. League median vs LHB: 0.451 EB/PA.

His raw rate vs LHB (0.374) 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 RHB86 PA0.471

vs RHB: shrunk estimate 0.471 EB/PA, 50% probable range 0.450 to 0.492, based on 86 plate appearances. Raw (unshrunk) rate: 0.549 EB/PA. League median vs RHB: 0.435 EB/PA.

His raw rate vs RHB (0.549) 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.

0.4000.4250.4510.4760.502
← betterworse →
Below league medianAbove50% probable rangeHis raw rateMiddle half of the league

His split is about typical for a lefty arm (median 0.038). Against righty 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 up the middle off him most often, but they do the most damage to the pull side.

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 Robby Ahlstrom this season is drawn where it landed.
hit · out
EBlowhigh
vs Yohendrick PiñangoHome run
105 mph · 30° · worth 3.9 bases
06/27 vs Blue Jays
vs Mike TroutHome run
111 mph · 23° · worth 3.6 bases
07/08 vs Angels
vs Brenton DoyleHome run
100 mph · 31° · worth 3.4 bases
08/26 vs White Sox
vs Tristan PetersHome run
96 mph · 31° · worth 3.3 bases
08/26 vs White Sox
vs Jose SiriDouble
110 mph · 20° · worth 3.2 bases
08/12 vs Angels

Luck check

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 8 more bases than their contact off Robby Ahlstrom deserved, so his results have been unlucky so far.

Deserved by the contact he allowed59
Actually credited to batters67

Both bars count 111 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 6.08 · WHIP 1.43 · BABIP against 0.298 (Lg median 0.286)

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.