In response to notin's comment:
Attempting to turn a RP into a starter fails far more often than it succeeds.
The Rangers succeeded with CJ Wilson, and then ruined Neftali Feliz trying to replicate that success.
At this point, Bard has already turned himself into a non-tender candidate and a reclaimation project. He has almost no trade value because of this...
That is true Notin....most of those efforts are not successful, in part because relief pitchers are not starters, generally speaking, because they are not good enough to be starters. The Red Sox should take note of this and think long and hard before they try to convert some of their more successful RP into SP-like Junichi Tazawa.