NEW YORK -- The Mariners aren't sure who their starting pitcher will be against the Padres on Sunday afternoon in San Diego, but they are pretty sure it won't be right-hander Felix Hernandez.

Still hobbled with a sprained left ankle he suffered during a home-plate collision during Monday night's Interleague game against the Mets, the Mariners' ace has all but officially been scratched from his next start, which would have been in the road-trip finale.

"We're not counting on Felix for Sunday," interim manager Jim Riggleman said during his pregame media session on Wednesday. "We are going to be realistic and are making some plans around him not pitching on Sunday."

Left-hander Erik Bedard, whose start against the Braves last Friday night was cut short because of back spasms, threw a bullpen session prior to the series finale against the Mets, it went well, and if there are no repercussions from the session, he would start on Sunday.

He will throw again on the side on Friday at PETCO Park, just to make sure.

If Bedard is unavailable, knuckleball specialist R.A. Dickey, who pitched seven shutout innings against the Mets on Tuesday night, would start against the Padres.

Exactly when Hernandez will return to the rotation remains uncertain.

"We could go all the way to Thursday without disrupting the rotation," Riggleman said.

Hernandez, who has a 6-5 record and a 2.83 ERA in 16 starts this season, was one out away from qualifying for his seventh win in Monday night's series opener against the Mets.

The Mariners were leading the Mets, 5-0, in the fifth inning when, with two outs and Carlos Beltran on third base, a pitch bounced into the dirt and caromed several feet away from catcher Jeff Clement.

Beltran, Hernandez and Clement all reached home plate at the same time. Clement tried to make the tag himself, Hernandez straddled the plate and Beltran slid on the infield side of the plate to avoid the tag.

Hernandez tried to continue, but threw one practice pitch and had to be helped off the field.