He’s been on the 40 man roster for almost 4 years. He would need to be added to the 26 man roster, as he is out of options. The only alternative is DFA him. He’s very likely to clear waivers, since he hasn’t pitched much in the past few seasons, hasn’t pitched all that well on the rare occasion he does pitch, and has no options left.
The only other possibility - which the Sox could do but makes zero sense - is the 60 day IL. Unless he actually is hurt, this would be a bad, since all it does is delay the same decision above.
I suspect they DFA him and then assign him to the minors if/when he clears waivers. I don’t think Mata can refuse assignment, but I could be wrong. Anyone got some clarity on that?