Matt Cain slices his way onto the disabled list

A pre-game snack for Matt Cain has ballooned into a Giant headache as San Francisco placed the right-hander on the 15-day disabled list after a kitchen accident.

Matt Cain channeled his inner Jeremy Affeldt last week after he sliced open his finger with a knife while trying to make a sandwich before his scheduled start against the Padres.

The cut — initially ruled non-severe by manager Bruce Bochy — has not healed as expected, forcing Bochy to send Cain to the DL for just the second time in his career.

Long-man in the bullpen Yusmeiro Petit stepped in admirably in Cain’s absence, tossing six shutout innings while leading the Giants to a 6-0 victory over the Padres.

Petit got the start Monday night against Pittsburgh, throwing 4-1/3 innings in the Giants’ 11-10 13-inning win.

Reliever Jake Dunning was recalled to help the shore up the bullpen. Dunning, a 25-year-old righty, threw 2/3 of scoreless relief Monday.

The Giants continue their three-game series at PNC Park against the Pittsburgh Pirates Tuesday at 4:05 p.m.