Aroldis Chapman has been better than we expected

"Primarily, they fixed Chapman's sinker and are letting him use it. It's no longer just a four-seam fastball at 99 and a slider in the mid-to-high-80s."

"Chapman now has a consistent secondary fastball that tunnels just like his four-seamer, has the same speed as his four-seamer, but instead of four inches of rise has two inches of dip."

"Instead of his four-seamer leaking out over the plate for a hot-and-heavy meatball, he's been able to dial it in much more on the glove-side and use his sinker."

"We’ve been dreaming of days like this with Aroldis Chapman at the helm in 2025."

Aroldis Chapman has become a key closer for the Red Sox in 2025 after improvements in his pitching mechanics, particularly with his sinker. Previously, Chapman's pitching was highly erratic, characterized by a heavy reliance on a fastball and slider combo. The adjustments made in the pitching lab allowed him to develop a consistent secondary fastball that mirrors the four-seamer in speed but offers improved control. This shift has made him much more effective in the ninth innings, a significant change for the team.

Read at Over the Monster