Cubs Acquire Chafin, Osich from Diamondbacks, Red Sox

Until a few hours ago, the Cubs had been relying on the grace of Kyle Ryan as their sole bullpen left-hander. Lo, that is no longer the case: Per reports from Jon Heyman, the Cubs have acquired Andrew Chafin from the Diamondbacks for a PTBNL or cash considerations, and Josh Osich from the Red Sox for a PTBNL.

Chafin has been a consistently useful pitcher over the course of his career, accruing 4.0 WAR over six seasons prior to this one. Though he sports an ugly 8.10 ERA in 2020, his more reasonable 3.88 FIP suggests that there has been some amount of bad luck affecting him over his very small sample of work — he has, after all, only thrown 6 2/3 innings so far this season. Though he’s walked more batters than is usual for him, his 30.3% strikeout rate is consistent with his career numbers. The same is true of the velocities on his three pitches. And aside from a disastrous appearance on July 29, when he failed to record an out and allowed three runs on a homer and a double, Chafin really hasn’t been all that bad.

Chafin has been on the Injured List since August 19 with a left finger sprain. According to Heyman, the D-backs will pay Chafin’s salary down to the minimum, hoping for a “low-level prospect” to come back to Arizona should Chafin make a quick return from his injury, which is clearly what the Cubs expect. When Chafin does come back, he should certainly be an improvement over Ryan.

The 31-year-old Osich, who has seen 15 2/3 innings of action this season, doesn’t have Chafin’s track record of success, and has already allowed an unfortunate six homers over his limited playing time this season. He does, however, have good strikeout numbers, particularly against left-handed batters, and doesn’t issue an overwhelming number of walks. That hasn’t translated into great results so far — and right-handed batters have a career line of .292/.367/.525 against him, which is worth considering in the age of the three-batter minimum. But unlike Chafin, who will be a free agent at the end of this season, Osich won’t hit free agency until 2023 and still has a minor league option, allowing the Cubs some vaunted roster flexibility.

The Cubs bullpen has struggled this season, with the team ranking 25th in reliever WAR. Cubs relief pitchers have particularly struggled when facing left-handed hitting, posting a collective 5.59 ERA and 5.26 FIP, the latter number third-worst in baseball. Ryan, who was fairly effective for the Cubs last year, has been the lone lefty in the bullpen for much of the season due to the injury to Brad Wieck, and has largely floundered in his 10 2/3 innings.

Ahead of the deadline, Theo Epstein named acquiring bullpen arms, specifically bullpen arms who can face left-handed hitting effectively, as a priority for the team. In the acquisition of Chafin and Osich, they’ve done just that. Neither Chafin nor Osich is what one might describe as an impact arm. But if the Cubs were looking to address their clearest area of weakness without having to give up much of anything in return, then the acquisition of Chafin and Osich could be viewed as a satisfactory outcome. Will they make the Cubs bullpen great, or even good? Probably not.