The Cubs have not had too many effective lefthanders in the bullpen this year.
They’re going to try a converted starter in the pen, as they have acquired lefty Derek Holland from the Giants. Per a press release from the team, this was a cash transaction, witn an unspecified amount of cash going in each direction between the Cubs and Giants.
Holland had a pretty good year in 2018 for San Francisco (3.57 ERA, 1.290 WHIP, 2.1 bWAR) but was demoted to the Giants bullpen after some bad starts early this year.