The Red Sox have made their first big league free agent signing of the offseason, inking former Tampa Bay Rays right-hander Cooper Criswell to a one-year deal.

According to ESPN’s Jeff Passan, the deal is for $1 million.

Criswell appeared in 10 games for the Rays last season and posted a 5.73 ERA over 33 innings. The 27-year-old was used exclusively in a bulk relief role, going at least two innings in all of his outings and at least four innings on four separate occasions. He also made 23 appearances in Triple-A, including 17 starts, and posted a 3.93 ERA in 84.2 innings at that level.

Originally selected in the 13th round of the 2018 MLB Draft by the Los Angeles Angels, Criswell also made one start each in 2021 for the Angels and in 2022 for the Rays before getting his first extended MLB run last year.

Criswell was designated for assignment by the Rays following the season and is expected to provide additional bullpen depth for the Red Sox. Given Boston’s logjam with right-handers Justin Slaten (Rule 5 pick), Mauricio Llovera and Bryan Mata (both out of options) all needing to stay on the MLB roster, Criswell provides an added benefit of being someone the club can option to Triple-A and bring up as needed.

With the signing, the Red Sox 40-man roster now stands at 39.