Logan Webb’s unconventional sweeping slider, often described as a “backwards sweeper,” showcased an unusual split in performance during the 2025 season. While the pitch proved exceptionally effective against left-handed hitters, it struggled considerably against right-handed batters. Webb’s usage of this pitch was a significant factor in him achieving a career-high 5.5 WAR in 2025, marking his fifth consecutive season with at least four wins. His distinct approach and reliance on this sweeping slider merit a closer look to understand why it thrived against lefties yet faltered against righties.
Webb’s Sweeping Slider Dominates Lefties but Falters Against Same-Handed Batters
Throughout the 2025 season, Webb consistently deployed his sweeping slider against left-handed hitters, making it one of the most frequently used pitches in right-on-left matchups. Among right-handed pitchers who threw at least 100 such sweepers, Webb ranked 11th in run value added per 100 pitches and threw an impressive 400 of them. His whiff rate was also notable, placing 15th in major league rankings, on par with top prospects like Paul Skenes but with much greater usage.
However, Webb’s pitch told a different story against right-handed hitters. Despite throwing the sweeper just as often, he ranked 75th out of 91 pitchers who used it over 100 times in right-on-right situations, indicating significant struggles. His run value added against these batters was below average, and alarmingly, his whiff percentage was nearly identical against both lefties and righties, which defies typical platoon advantage trends where pitchers usually generate more swings and misses against opposite-handed batters.
How Webb’s Approach Shifted Between Lefties and Righties
Webb’s strategy involved using his sweeper heavily to initiate counts against left-handed hitters, throwing it 162 times on 0-0 counts in 2025. This approach was highly effective, as his pitch consistently targeted the strike zone’s ideal locations early in counts, earning high command grades and contributing to his ability to quickly get ahead. Even when he reached two strikes against lefties, Webb maintained a similar location strategy, relying on the pitch’s sharp movement to keep hitters off balance.
In stark contrast, when facing right-handed batters, Webb rarely repeated this approach. The sweeper’s early-count locations against righties were scattered and poorly placed, with a Waste Miss Percentage of 47.1% compared to just 29% versus lefties—a stark indicator of wasted pitches outside the strike zone that hurt his overall effectiveness. His command grade against righties to start the count was low, reflecting the inconsistent and less disciplined usage of the pitch in these scenarios.
Command Woes and Pitch Placement Problems Against Righties
Even after falling behind in counts, Webb’s strategy against righties didn’t improve markedly. While he occasionally moved the sweeper further off the plate with two strikes, the command remained poor, receiving a command grade of only 40 and an overall grade just slightly above failing. This poor location likely contributed to Webb inducing a career-low swinging strike rate with his sweeper against right-handed hitters in 2025.
Comparatively, in 2024 Webb displayed better precision with the sweeper in two-strike counts against righties, avoiding many glaring mistakes and allowing him to generate more effective outcomes. The decline in sharpness in 2025 might have been influenced by an expanded pitch mix, including modifications to other breaking balls like cutters, which some pitchers have said can diminish the feel for their other offerings.
Contradictions in Webb’s Overall Performance Against Lefties
Despite the sweeper’s success in setting up advantageous counts against left-handed batters, Webb’s overall numbers against them in 2025 were surprisingly poor—among the worst performances of his career up to that point. This inverse relationship raises questions given that lefties are traditionally the tougher matchup for right-handed pitchers.
Webb’s difficulties were partially explained by his secondary pitches, especially his changeup, which he relies on with two strikes to put away left-handed hitters. While effective in previous years, his changeup command and location suffered in 2025, leaving it more hittable as it drifted out of the strike zone. This decline resulted in fewer swings and misses and placed extra pressure on his other pitches.
Details on Webb’s Secondary Pitches and Their Impact
In 2023 and 2024, Webb managed an effective cluster of low-envelope changeups, minimizing wasted pitches and pitches that left the strike zone’s danger areas. Those seasons reflected strong command, good location, and overall efficiency in finishing at-bats. The 2025 season diverged, as his changeup leaked further out of the zone, diminishing its put-away ability and reducing chase rates from hitters.
Because the sinker, Webb’s signature pitch, performs markedly worse against left-handed batters and fails to induce strong whiff rates on that side, Webb was forced to increase his reliance on four-seamers and cutters in those critical moments. Unfortunately, neither of these offerings consistently delivered. His four-seamer was generally ineffective, suffering from both mediocre shape and location that failed to fool hitters high in the zone. The cutter fared slightly better but served more as a setup pitch than a dominant strikeout weapon.
The Sweeper’s Role Within Webb’s Arsenal and Results Against Righties
Against right-handed hitters, Webb’s sweeping slider’s poor locations were somewhat mitigated by his excellent command of other pitches, particularly his changeup. This pitch remained effective despite occasionally erratic placement, allowing him to rebound and succeed despite struggles with the sweeper. His willingness to attack the zone with sinkers complemented this approach, forcing hitters to contend with multiple challenging pitches.
Thus, although the sweeper failed to consistently generate whiffs or favorable counts against righties, Webb’s broader repertoire compensated for these deficiencies, leading to better overall results compared to his hits lefties experience despite the sweeper’s dominance in that matchup. This creates a complex dynamic where the pitch-level split clashes with the pitcher-level success rates.
Insights on the Variability and Noise in Platoon Splits
Platoon splits and pitch usage statistics are inherently noisy and influenced by sample sizes, pitch mixes, and execution variability. Webb’s 2025 season illustrates this: while he excelled with his sweeping slider against lefties and faltered in command with his changeup, the opposite pattern showed up against righties. These contradictions highlight how even a pitcher with a polished arsenal can see fluctuating effectiveness influenced by seemingly small changes in insight, command, and sequencing.
The analytical model from FanGraphs Lab was instrumental in uncovering these nuances, particularly illuminating the value and uniqueness of Webb’s right-on-left sweeper—a gem that might have otherwise gone unnoticed due to the complexity of platoon splits and the interplay among pitches.
Looking Forward: Adjustments and Potential Developments for Webb
Webb’s sweeper success in getting ahead of lefties during early counts was among the highest of his career, indicating that regaining improved feel and command on his changeup could drastically change his effectiveness against left-handed batters in future seasons. Adding more sinkers into the mix against lefties may also benefit Webb, as the pitch is traditionally more challenging for left-handed hitters than evidence from recent results suggests.
While the model does not capture every aspect of Webb’s pitching or the many situational variables in baseball, it provides valuable context for his divergent platoon performances. Understanding why this backwards sweeper turned into a weapon against left-handers but not righties helps explain Webb’s puzzling overall splits, underscoring the intricate balance pitchers must maintain in pitch location, sequencing, and execution.
Kevin Gausman speaks about adding a cutter to his arsenal on @SNJeffBlair pod@PitcherList @TJStats pic.twitter.com/0pbzQ8VLDQ
— Dynasty Junkie (@PeepMySlashLine) February 4, 2025
