Fresh off a 2-5 Western road trip and a much-needed day off, the Mets return to action tonight at Citi Field when right-hander Bobby Parnell takes on the Giants in the opener of a four-game series.

Parnell is making just his second major-league start since being converted from the bullpen to take the place of the injured Jonathon Niese. Parnell allowed two runs on four hits and three walks in just 2 1/3 innings last Saturday in San Diego in his debut, and he will be limited to roughly 85 pitches again tonight.

Parnell will take on lefty Barry Zito, who has been somewhat resurgent lately as San Francisco chases both the Dodgers in the NL West and the wild card. Zito is 8-10 with a 4.40 ERA. Here is the 53-61 Mets’ order for the 7:10 p.m. game:

Angel Pagan CF

Luis Castillo 2B

David Wright 3B

Gary Sheffield LF

Jeff Francoeur RF

Fernando Tatis 1B

Omir Santos C

Anderson Hernandez SS

Robert Parnell RHP (2-4, 3.94)