Both pitchers are coming off of subpar 2015 campaigns. Miley posted a 4.46 ERA with a 147/64 K/BB ratio in 193 2/3 innings. The Red Sox acquired him from the Diamondbacks in December last year in exchange for Rubby De La Rosa, Allen Webster, and Raymel Flores. Kelly compiled a 4.82 ERA with a 110/49 K/BB ratio over 134 1/3 innings. He joined the Red Sox along with Allen Craig in exchange for John Lackey, Corey Littrell, and cash in a trade at the deadline in July 2014.
Miley is owed $6 million in 2016 and $8.75 million in 2017 before being eligible for free agency, assuming he’s bought out at $500,000 ahead of the 2018 season. Kelly is entering his third and final year of arbitration eligibility after earning $603,000 this past season.
The Red Sox have already bolstered the bullpen this offseason, bringing flamethrowing closer Craig Kimbrel over from the Padres, bumping Koji Uehara into the set-up role. They also made a big improvement in the rotation, inking David Price to a seven-year, $217 million deal.