Liriano has great numbers overall for Pirates, but he has not been as consistent as he was early on with a couple of recent clunkers vs. Rockies and Giants. Yes, those were sandwiched between allowing a total of one run in three other starts, but which Liriano shows up today and, more importantly, do you want to pay this premium to find out? Remember that Milwaukee is hitting lefties well right now, batting .274 and averaging a whopping 6.48 runs per game against them the last 10.
Peralta has gotten better as the season has gone on for Brewers, and he has allowed three runs or less in 11 of his last 13 starts. Pirates may be winning, but they are still only batting .239 vs. righties overall and this will be their first time ever facing Peralta.