Tyler Mahle made the splitter his main pitch in seven innings against Philadelphia

Brandon Marsh saw two fastballs before Tyler Mahle turned to the splitter. One splitter missed for a ball. Marsh swung through the next, at 88.5 mph. Then he missed another, at 89.4, to end the first inning.

Philadelphia had already collected three hits and a run. Mahle had needed a play at the plate to stop another runner from scoring. The strikeout did not erase that difficult start, but the pitch that finished it became the defining feature of the six scoreless innings that followed.

Mahle threw 55 splitters among his 95 pitches in Game 2 of the National League Wild Card Series. He completed seven innings with six hits, one walk, six strikeouts and one run allowed. When he finished, Atlanta led 3–1. Philadelphia’s tying runs in the eighth came against the bullpen, and the Phillies went on to win 4–3.

His outing was not built on an untouched fastball or an absence of hard contact. It rested on a much heavier splitter share, a fastball that still collected called strikes, and enough quick outs to carry that combination through seven innings.

The splitter increase survives a fairer comparison

The splitter accounted for 57.9% of Mahle’s pitches. Across his full regular-season tracking sample, it represented 29.7%. That comparison is striking, but the full season alone leaves out an important part of his context.

In nine regular-season appearances for Atlanta, spanning August 7 through September 24, the pitch already made up 38.5% of his 824 tracked pitches. Game 2 therefore extended an existing pattern rather than introducing a pitch the Braves had barely seen him use.

Even against that Atlanta-only sample, the increase was 19.4 percentage points. His four-seamer fell to 34.7%, compared with 48.5% in the Atlanta sample. He threw only six cutters and one slider.

The distribution was not confined to one side of the plate. Left-handed batters received 38 splitters in 61 pitches; right-handed hitters saw 17 in 34. Opponent handedness can influence selection, but this outing’s reliance on the splitter appeared against both groups.

The data establishes what Mahle threw. It does not, without an attributable explanation from him or the coaching staff, establish why the plan changed.

One pitch supplied most of the misses

Philadelphia missed 13 times in 35 swings at the splitter, a 37.1% whiff rate. That pitch supplied 13 of Mahle’s 15 total misses and finished five of his six strikeouts.

It also drew swings away from the zone. Baseball Savant classified 34 splitters outside the strike zone; Philadelphia offered at 20 of them, a 58.8% chase rate. Nine of the splitter misses came outside the zone and four came inside it.

The pitch averaged 87.3 mph, about one mph above its full-season average and roughly four-tenths above its Atlanta average. The four-seamer averaged 93.5. That difference in speed describes one of the contrasts hitters faced; it does not by itself prove identical early trajectories or explain every swing.

Nor did the fastball disappear. Mahle earned 10 called strikes with it, compared with six on the splitter. His lone fastball strikeout came at the end of Trea Turner’s seven-pitch plate appearance in the second: a 95.4 mph four-seamer on a full count.

The dominant selection still needed a supporting pitch.

The first inning was a problem he survived

Turner doubled on Mahle’s second pitch. Kyle Schwarber’s groundout moved him to third, and Bryce Harper’s ground-ball single brought him home. Alec Bohm then singled, putting runners at the corners with one out.

Bryson Stott hit a splitter back to Mahle, beginning the play that retired Harper at the plate. Marsh’s strikeout followed. Philadelphia’s inning contained three hits but ended with one run.

That sequence is important counterevidence to a story of effortless command. Mahle gave up contact and needed an out on the bases before the splitter supplied the inning’s final out. His best pitch also allowed both Harper’s and Bohm’s singles; using it more often was not the same as making it unhittable.

The later innings show why he could keep returning to it anyway.

The fifth illustrated the plan at its clearest

Mahle needed 11 pitches in the fifth. Turner grounded out on a splitter. Schwarber struck out on an 88.7 mph splitter after a plate appearance that included a fastball miss. Harper then saw a called-strike fastball followed by three splitters: a miss, a foul and another miss.

Two prominent left-handed hitters finished successive plate appearances without putting the ball in play. The fastball helped create the counts; the splitter finished them.

Mahle then completed the sixth in 14 pitches despite a Marsh single. In the seventh, he needed only eight. J.T. Realmuto’s strikeout came on three consecutive splitters, each between 86.4 and 86.6 mph. Turner’s lineout ended the inning and Mahle’s outing at 95 pitches.

Those quick later innings mattered as much to the seven-inning result as the strikeouts. Mahle used 50 pitches through three innings and only 45 across the next four.

Contact supplied a necessary qualification

Philadelphia put 21 balls in play against Mahle. Eight reached at least 95 mph, and the overall average exit velocity was 89.4 mph. The splitter accounted for 14 of those balls, averaging 87.5 mph off the bat.

Some hard contact became outs. Bohm’s sixth-inning groundout registered 106.3 mph. Realmuto’s fourth-inning lineout came off a cutter at 99.3 mph. Those outcomes belong in the explanation alongside the missed bats.

Mahle’s achievement was holding that mix of contact and strikeouts to one run while allowing only one walk. It was not a demonstration that every ball in play was harmless, nor does one start establish that a near-58% splitter share is the correct approach against every lineup.

What to carry into the next outing

The splitter was already becoming more prominent in Mahle’s Atlanta sample. In Game 2, he pushed its share higher, used it against hitters on both sides and returned to it to finish five strikeouts. His fastball remained useful for called strikes, and a succession of short later innings kept the workload manageable.

The next test is whether that selection persists against a different lineup and whether hitters continue chasing the splitter outside the zone. For this outing, the record is clear: it was the main pitch in a seven-inning performance, with both the swing-and-miss value and the contact risk that came with using it 55 times.

The other side of Game 2

Read our separate analysis of Cristopher Sánchez’s changeup and seventh-inning traffic.