3. Wade Davis 2017
After the departure of rental closer Aroldis Chapman in the 2016 offseason, the Cubs filled the gap when they traded slugging outfielder Jorge Soler to Kansas City for closer Wade Davis. The stoic right-hander was coming off three straight seasons of impressive sub-two ERA bullpen work. Although he only had one year left on his deal, Davis made it count for the Cubs with a 2.30 ERA in 58.2 innings of work and an almost perfect 32 saves out of 33 attempts. The most triumphant moment of Davis' short Cubs career was striking out Bryce Harper at the end of a 9-8 nail-biter against the Nationals to advance the Cubs to the 2017 NLCS.