Shawn Trewartha | May 11, 2026

When Rockies director of pitching Matt Daniels and pitching coach Alon Leichman arrived in 2026, they inherited one of the most difficult assignments in North American sports: solving the Coors Field pitching problem. They also walked into a situation where the bar set by the 2025 staff was, frankly, hovering just a hair above the dirt.

Early in the season, even with the Rockies’ record hovering near the bottom of the league, the new pitching department appears to be delivering on its goal of putting the staff on a path toward growth. The improvement is evident in the numbers: after finishing last in strikeouts per nine innings (6.99) in 2025, the Rockies have raised that mark to 7.94 in 2026. Their walks per nine have also taken a significant step forward, climbing from 26th in the league to 9th.

Perhaps most notably, the pitching staff’s fWAR has already surpassed its entire 2025 total in fewer than 40 games and figures to only keep increasing. While there is still a lot of growth to be had, the improvement has been a welcome surprise for a struggling fan base. 

Looking at the staff as a whole, two key philosophical changes appear to be driving the improvement, both of which were emphasized throughout Spring Training. The first was expanding pitch arsenals and reducing reliance on the four-seam fastball. In 2025, Rockies pitchers threw four-seamers 39.5% of the time, the third-highest rate in the league; in 2026, that figure has dropped to 28.8%, now the seventh-lowest.

The second was an increased willingness to lean into breaking pitches, particularly those with downward movement, an approach well-suited for Coors Field, despite past hesitancy. This shift is evident in the increased usage of sliders, which have also shown an average gain of 9.6 inches in vertical movement across the staff.

While it is interesting to see what the staff is doing as a whole, I wanted to take a more granular look at the two pitchers who have improved the most year over year, Chase Dollander and Antonio Senzatela. The goal was to pinpoint the mechanical adjustments introduced by the new staff that are driving these strides in improvement.

Chase Dollander

All of the surface level metrics for Chase have improved so greatly that it would be a chore to list them all out. So as a good catch-all, his ERA+ currently sits at 142 versus just 72 last year. He’s clearly rounding into the pitcher Rockies fans hoped he would become.

Pitch Mix

Unlike most of the pitching staff, Chase’s pitch mix has not changed all that much from 2025. He still relies mostly on his plus four seamer although the usage has decreased from 49% to 37%. Picking up a lot of that usage has been the two seamer which has been thrown 23% of the time. So he’s still a primarily a fastball thrower, an approach which is hard to argue with when the fastball has a 31% whiff rate and .139 expected batting average against. 

While the fastballs are impressive, changes to the secondary pitches are also greatly aiding in his newfound success.

Movement Profile

Chase’s slider has changed so dramatically from Year 1 to Year 2 that it is almost a different pitch entirely. The spin axis has shifted from 155° to 110°, a massive 45° change. This, along with a 5% increase in spin rate, has resulted in a sharper, more downward biting breaking pitch, as reflected in the pink circles above. This new slider has a 32% whiff rate, 10 percent greater than it was in 2025. And while the potential for hard-hit balls is still a concern, the pitch-specific slugging percentage on the slider has improved from .614 to .381.

Another change was to the sinker and changeup. Last year the two pitches had very similar movement profiles albeit with a 8 MPH difference between the two. This year Chase has increased his average velocity on his sinker by 1.3 MPH, and is getting 2 additional inches of armside movement. This creates an additional layer of deception for both pitches, and the results are beginning to show on the field.

Pitching Mechanics

The Rockies’ pitching lab in Arizona has been working overtime with a more analytically driven front office at the helm. One goal of the pitching lab is to dial in pitching mechanics to better optimize pitch success. For Chase, that has resulted in roughly three additional inches of extension. His arm slot has also dropped by three degrees, and his release point has shifted closer to home plate rather than toward the third base side.

These changes have led to a more repeatable delivery, as evidenced by the much tighter average release points of his pitch types in 2026 compared to 2025. This repeatability is essential for pitch tunneling and deception.  

Antonio Senzatela

When discussing MLB surprise stories of 2026, Antonio Senzatela is at the top of everyone’s list. He went from arguably the worst pitcher in baseball last year to a top reliever in the game with a 1.11 ERA and 0.82 WHIP. Working in the bullpen has made all of the difference for Senzatela. Along with a more appropriate pitch mix and a revitalized fastball, he has gone from a financial ball-and-chain to an asset.

Pitch Mix

Senzatela has never been a guy with a deep pitch arsenal. Throughout his career, he has mostly been a fastball/slider guy with a changeup and a curveball occasionally mixed in. Unfortunately for him, his slider never returned to quality form after his Tommy John surgery, and his fastball was losing velocity with age.

Finally, in 2026, he has a reliable secondary pitch to replace the slider: the cutter. While using the cutter 29% of the time, Senzatela has lowered his fastball usage to 38%, more fitting to the Rockies’ new philosophy. He is also incorporating a sinker more often, and maintaining the curveball as a breaking option 10% of the time.

Movement Profile

Senzatela used his sinker only sparingly in 2025, to terrible success. Its pitch-specific batting average was .750, and its slugging percentage was 1.750. This year, with the help of the pitching lab, he has redesigned his sinker so that it averages about 4 more inches of armside horizontal break and over 5 more inches of downward break. He achieved this by shallowing the spin axis by 4° for a more tumbling movement, and he also increased the spin rate by 9.3%, allowing for more overall bite. After the change, his sinker is achieving a much more manageable .333 BA and .333 SLG.

This increased spin rate is seen across pitches, allowable due to his more limited role as a reliever. The spin rate has increased 4% on his fastball, leading to a better “rising” effect of his high rail four-seamer, and it has increased 1.5% on his cutter and 7.26% on his slider, both resulting in more aggressive glove side action.

Pitching Mechanics

Standing at 6-foot-1, Senzatela’s extension was never going to rival pitchers with taller frames. Even so, his average extension last year was 6.1 feet, and he has increased that to 6.3 feet this season. Like Chase, his arm slot has dropped by 2°, but unlike Chase, he has shifted his release point further toward third base. Combined, these changes create an over eight-inch difference in release position for his cutter specifically.

Senzatela also consolidated his release points, though there is still a noticeable spread. That change is still resulting in more deception and less predictability out of the hand.

Building Toward Something Sustainable

This is not to say everything has been perfect. Several pitchers on the staff have underperformed early in the season, and others have regressed from solid 2025 campaigns. The focus on Antonio and Chase is meant to highlight how the organization is tailoring its approach to two very different profiles, one early in his career, refining his arsenal, and another later in his career, working to rediscover past success. If they can replicate that kind of development year over year, there is a clear path to building a playoff-caliber rotation, even at Coors Field.

Written by Shawn Trewartha.