We really don't know yet, sammy.
Hennessey isn't eligible to return yet. Foppert has skipped his last two starts.
Cain isn't on the 40 man roster, so they'd have to make a couple moves in order to bring him up.
So, I'd surmise that Fassero might make a spot start, or one of Aardsma or Valdez might get called up at the expense of one of the bullpen guys.
But, we won't know for until tommorow.