CHICAGO -- The Cubs acquired Andrew Chafin last summer in an effort to shore up the bullpen's production against left-handed hitters. Chicago will now keep the lefty in the relief picture for at least the 2021 season.

The Cubs reached an agreement with Chafin on a one-year deal with a mutual option for 2022, the team announced on Friday. Chicago also announced the signings of outfielder Joc Pederson and right-hander Trevor Williams.

Terms of Chafin's pact with the Cubs were not disclosed, but a source told MLB.com that it includes a $2.25 million salary for '21, with a $5.25 million mutual option (or $500,000 buyout) for '22. Chafin can also earn up to $500,000 in performance bonuses in each of the '21 and '22 seasons, based on games pitched).

At the Aug. 31 Trade Deadline during last year's abbreviated 60-game season, the Cubs reeled in Chafin from the D-backs in exchange for a player to be named (Chicago later sent Minor League infielder Ronny Simon to Arizona). At the time, Chafin was on the injured list, dealing with a sprained finger on his left hand.

Chafin was activated before the end of the season and logged three innings across four appearances for the Cubs, striking out three and allowing one run. Overall, the 30-year-old lefty had a 6.52 ERA in 15 outings (9 2/3 innings) in his injury-marred campaign.

Prior to '20, Chafin had been a steady presence in Arizona's bullpen for five-plus seasons. He has fashioned a 3.67 ERA in 341 career MLB games, piling up 291 strikeouts in 274 2/3 innings with a 2.47 strikeout-to-walk ratio. Chafin has also held lefty batters to a .230 average and .616 OPS in his big league career.

At the moment, Chicago's crowded bullpen field is heavy on right-handers, so Chafin adds a veteran southpaw to the mix. Beyond Chafin, the Cubs also have an experienced lefty in Kyle Ryan, plus Brad Wieck. Lefty prospects Brailyn Marquez and Justin Steele are also on the 40-man roster, but are starters by trade.