The Red Sox added a proven starting pitcher who can bolster them for the 2022 stretch run and perhaps beyond, signing lefty James Paxton to a one-year deal that includes a two-year club option for the ¡®23 and ¡¯24 seasons. The club did not announce financial terms, but a source told MLB.com the deal is worth $10 million.

Paxton, a lefty, had Tommy John surgery in April and likely won¡¯t pitch for Boston until midseason at the earliest.

If the options are picked up, the deal could wind up being worth close to $35 million.

¡°We do expect to see him sometime in the second half of the season if all goes well,¡± said Red Sox chief baseball officer Chaim Bloom. ¡°We're hopeful that when he does come back, he's going to be able to give us a lift.¡±

Chad Dey of SportsNet in Canada and ESPN¡¯s Jeff Passan were first to report the agreement, which is pending a physical.

Paxton made one start for the Mariners in 2021, allowing one run in 1 1/3 innings before leaving the game with elbow discomfort. Soon thereafter, the decision was made for him to have Tommy John surgery.

The 33-year-old spent his previous two seasons with the Yankees, including a 2019 season in which he went 15-6 with a 3.82 ERA. Paxton went 41-26 with a 3.42 ERA over the first six years of his career with Seattle, including a no-hitter on May 18, 2018, in his home country of Canada against the Blue Jays.

In 2017, Paxton came into his own for the Mariners, going 12-5 with a 2.98 ERA in 24 starts.

From 2017-19, Paxton was one of the best lefty starters in the game, posting a 38-17 record with a 3.54 ERA, holding opponents to a .230 average while striking out 550 over 447 innings.

¡°We've seen before injuries really started to impact his career, he was one of the better left-handed pitchers in the American League,¡± Bloom said. ¡°And, if he gets back to that, he could provide a huge boost for us in the second half.

¡°And we also have the ability, if all goes well coming here, to control him for a couple years after that. That was a big part of this deal for us -- adding someone who might be able to help us down the stretch this coming year but then also be a big part of what we're doing in the years ahead.¡±

Once Paxton returns from his rehab, he will join a Boston rotation that includes Chris Sale, Nathan Eovaldi, Nick Pivetta and the recently-acquired Michael Wacha.