After starting the 2015 season as a bona fide mess. The Texas Rangers bullpen, through trade deadline acquisitions of power arms Sam Dyson, and Jake Diekman, plus the emergence of Shawn Tolleson and Keone Kela as closer and power set-up man, transformed into a well oiled machine in the latter stanzas of the season.
After ranking 27th, 28th, and 27th for bullpen ERA in May, June, and July, the Rangers bullpen rebounded in impressive fashion. Posting the 13th best bullpen ERA in August and then finishing 1st in all MLB for September.