The Sox were looking for a powerful backup, preferably a hard-hitting left-handed hitter. Chapman fits that bill. He was the original “stuff” guy, long before speed became such a big factor in baseball. Since being drafted by the Reds in 2010, Chapman ranks 14th in the majors with an average pitch speed of 99.1 mph. It seemed like Chapman was on his last legs after a forgettable season with the Yankees in 2022 in which he posted a 4.46 ERA in 36⅓ innings. He had been dealing with a shoulder injury and had lost the closer role to Clay Holmes upon his return.

Chapman’s character has been under scrutiny since 2015, when he was allegedly involved in a domestic dispute in which his girlfriend accused him of pushing and choking her. During the incident, Chapman admitted to firing shots in his garage. Although no charges were filed due to insufficient evidence, Major League Baseball conducted its own investigation and suspended him for 30 games.

Chapman’s departure from the Yankees also raised questions. He wasn’t guaranteed a spot on the postseason roster after a difficult 2022 season. In response, Chapman skipped a mandatory practice at Yankee Stadium before the ALDS game against the Guardians, opting instead to stay at his home in Miami. This led the Yankees to conclude that Chapman’s tenure was over.

With that stuff running out, Chapman began incorporating a sinker in 2023 to fit his four-seam fastball/slider mix. He threw his sinker 16.2 percent of the time this year, compared to just 5 percent in 2022. It has paid off, as Chapman posted a 3.09 ERA in 2023, 103 strikeouts over 58⅓ innings, his highest Strikeout total since 2015 (116) with the Reds.

With Chapman, the Red Sox have a proven veteran with a powerful left arm that they have been looking for for years. They experimented with Bailey Horn and Cam Booser in 2024. Horn had been designated for assignment by the White Sox, and Booser, at 32, was in his first year in the big leagues. Neither was an established big league backup player. Chapman not only has the resume, but also postseason experience, which will hopefully help the Red Sox return to the playoffs after missing October baseball four times in the last five years. Chapman is prone to walks and has a career walk rate of 12.6 percent, including 14.7 in 2024. But when he’s in the zone, he’s still among the best in baseball.

Julian McWilliams can be reached at [email protected]. Follow him @byJulianMack.