How do you get over a series loss in a four-game series, including losing on a walk-off homer when you have the lead? Face a bad team of course. That is a slight misrepresentation - yes, the Cardinals were winning, but the expectation was that the Mets would be able to tie it up, since they had a runner on 2nd and nobody out. But still. Not the best way to lose. And as we saw in the Baltimore series, the Cardinals are perfectly capable of losing to bad teams.
The Pirates arguably have two good position players: Bryan Reynolds, NL All-Star last year, and Ke’Bryan Hayes, probable NL Gold Glove winner once he manages to take one from Nolan Arenado.