As I said a few pages back, the Sox have eight pitchers--Crawford, Kluber, Sale, Winckowski, Pivetta, Houck, Whitlock, and Bello--with either significant innings or starter potential or both. Winckowski hasn't started, but he's pitched 14 innings and several times gone 3 innings. Bello only has 2.2 lousy innings (5 ER's), but has shown starter potential. The other six have all started at least two games.
My point now is that it would make sense to move Kluber, who so far has 4 losses and an ERA of 8.50, to the bullpen or to "6th starter," either or which would limit his starts. Cora would still have six viable starters (assuming Bello is viable): Crawford, Pivetta, Houck, Sale, Whitlock, and Bello. No other Sox pitcher (besides Kluber) has more than one loss.
Too bad Kluber is being paid $10M, but last year the Sox paid Sale even more than that and for fewer innings (and less damage to the Sox).
The real point is that a starter can lose a game before the hitters have a chance to hit or the bullpen has a chance to save a game. And the Sox have six other starters plus Paxton trying to make his way back.