Tazawa has been brilliant since switching exclusively to relief, putting together 112-1/3 innings of 2.48 ERA ball with nearly seven times as many strikeouts as walks over the last two seasons. Tazawa briefly moved into the closer role without recording a save following injuries to Joel Hanrahan and Andrew Bailey in 2013, but eventually ceded the spot to Koji Uehara, who remains closer heading into 2014.
While Tazawa has been under team control since signing in 2008, with his major-league debut coming in 2009, Tommy John surgery delayed his emergence, and he just last season finished accruing the three years of service time that make players arbitration-eligible. The Red Sox control Tazawa through 2016, but, based on his $1.275 million salary for 2014, they will never have to pay him very much unless he moves into the closer role: first-year arbitration payments tend to reflect around 40 percent of perceived free agent value, meaning the Sox and Tazawa agree that, at this stage, he's likely worth just about $3.25 million or so as a free agent setup man with relatively limited experience.
The Red Sox have until 1 pm to finalize deals with their remaining arbitration-eligible players: Andrew Miller, Jonathan Herrera, and Mike Carp. Miller will most likely pull in the most money of the bunch, while we already know there is "zero chance" that Carp is extended, meaning he will sign a deal just for 2014.