Feb. 2: C Tyler Heineman acquired from Mets for cash considerations; RHP Max Castillo designated for assignment
In a move designed to bolster their catching depth, the Sox added the 32-year-old Heineman. Connor Wong is expected to be Boston’s primary catcher again in 2023. Heineman could challenge Reese McGuire for the backup spot, or serve as injury protection. Heineman split last season between the Pirates (three games) and Blue Jays (19 games), making 16 starts behind the plate and hitting .237. The switch-hitter has played in 104 career games. Castillo had been added as a waiver claim from the Royals on Jan. 2.

Jan. 31: INF/OF Romy Gonzalez claimed from White Sox; RHP Zack Weiss designated for assignment
The Red Sox added some possible depth to their bench by adding Gonzalez in a waiver claim from the White Sox. The 27-year-old has played in 86 career games with the White Sox (2021-23), making 46 starts at second base, seven in right field, four at shortstop, three at third base and three in left field. The right-handed hitter has batted .222 (51-for-230) with 11 doubles, three triples, five home runs and seven stolen bases. In 2023, Gonzalez played 44 games with the White Sox before being placed on the injured list on July 2 due to right shoulder inflammation.

To make room on the 40-man roster, Weiss was designated for assignment. The 31-year-old righty pitched in six games for Boston last seson, recording a 2.08 ERA with eight strikeouts.

Dec. 30: INF Vaughn Grissom acquired from Braves for LHP Chris Sale
The Red Sox shipped the veteran Sale to Atlanta for Grissom, a promising young infielder who should have a solid opportunity to assume the vacancy at second base.

Sale, a seven-time All-Star, waived his no-trade rights to make the deal possible. With him out of the mix, Boston’s starting rotation remains a work in progress — with new free-agent signee Lucas Giolito and Brayan Bello, the team’s best young pitcher, certainties and a mix of right-handers Nick Pivetta, Tanner Houck, Garrett Whitlock and Kutter Crawford all potential options as well.

Dec. 29: RHP Lucas Giolito agrees to two-year, $38.5 million deal
The Red Sox made a significant addition to the rotation by coming to terms with Giolito on a two-year pact, a source told MLB.com’s Mark Feinsand. The deal, which has not been confirmed by the club, includes an opt-out after 2024.

Dec. 13: RHP Cooper Criswell signs one-year deal
The Red Sox added some bullpen depth with the signing of Criswell, who pitched 10 games for the Rays in 2023. In 33 innings, the righty allowed 23 runs on 40 hits, fanning 27 and walking 11.

Dec. 11: Seven non-roster invitees added to the 2024 Spring Training roster
Here are the non-roster invitees the Sox added to the Spring Training roster: Pitchers Jorge Benitez, Cam Booser, Frank German and Helcris Olivarez, infielder Jamie Westbrook, outfielder Mark Contreras and infielder/outfielder Eddy Alvarez.

Dec. 8: OF Tyler O’Neill acquired from Cardinals for RHPs Nick Robertson and Victor Santos
In O’Neill, the Red Sox added a right-handed bat they were seeking in the outfield. O’Neill is a two-time Gold Glove Award winner, and he finished eighth in the National League Most Valuable Player Award voting in 2021. O’Neill is coming off a pair of injury-plagued seasons for the Cardinals in which his offensive performance dipped. Robertson and Santos were considered depth arms in Boston’s farm system. More >>

Dec. 6: RHP Justin Slaten acquired in Rule 5 Draft trade with Mets
Technically, the Red Sox didn’t pick anyone in the Major League phase of the Rule 5 Draft at the 2023 Winter Meetings. In reality, they did. Shortly after the Draft ended, the Sox acquired Slaten from the Mets in exchange for Minor League lefty Ryan Ammons and cash considerations.

The Mets nabbed Slaten from the Rangers with the seventh overall pick in the Rule 5 Draft — five slots ahead of Boston’s pick. He does carry a Rule 5 designation in Boston, meaning the Red Sox will have to keep Slaten on the 26-man roster all season.