I'm looking over the Astros' stats so far, and this caught my eye:
player G IP H ER HR BB K
Fiers 9 46.2 54 28 18 17 38
Musg 9 46.1 55 29 9 17 37
Basically, their stats are almost exactly identical except that, as many homers as Musgrove has allowed (1.7 per 9 IP), Fiers has allowed TWICE as many.
Ideally, you'd send Musgrove down to work on some things in AAA, but given the dearth of rotation options at the moment I think they might have to just hope he makes some adjustments and turns it around. Fiers, on the other hand, is a complete fucking wreck of a train that crashed into a dumpster full of flammable excrement. If Keuchel is able to make his next start, I really hope that Peacock displaces Fiers. Not that I expect Peacock to be great - I think the bullpen is his long-term home - but at least he can probably avoid giving up 18 HOMERS and a 1.52 WHIP in 46 innings.