WHAT IT MEANS: Jeremy Hefner, who is poised to be bounced from the rotation with Johan Santana due to return next weekend, showed he will remain a viable spot starter if the Mets need to give pitchers extra rest down the stretch.

Hefner allowed a leadoff single to Alexi Amarista in the first inning, but erased him by doubling up No. 2 hitter Will Venable. He ultimately limited his former organization to one run on five hits and no walks in a 74-pitch effort spanning six innings.

Hefner originally was drafted by San Diego in the fifth round in 2007 and exclusively was a Padres minor leaguer until being claimed off waivers by the Pirates and then by the Mets this past offseason.

The Mets beat the Padres 6-2 Saturday night at Petco Park.

Terry Collins said pregame that he expected Hefner now to be reassigned to the bullpen. Santana is scheduled to pitch three innings for the Brooklyn Cyclones on Sunday, then reenter the rotation next Saturday against the Braves at Citi Field.

WALK TALL: Mike Baxter -- a waiver claim from the Padres -- walked in all five plate appearances, matching the franchise record for walks set by Vince Coleman in a 16-inning game against the Pirates on Aug. 10, 1992. The last five-walk performance in the majors in a nine-inning game was by Philadelphia’s Ryan Howard in 2006.

Edinson Volquez walked four including Baxter, forcing in two runs, and Jordany Valdespin had a two-run double in a four-run second inning. Valdespin had been only 3-for-23 on the road trip entering that at-bat.

Daniel Murphy went 4-for-4 with a walk.

SPECIAL DELIVERY: Josh Edgin, now the lone lefty in the bullpen with Tim Byrdak landing on the DL, tossed a scoreless seventh despite a two-out error by Ruben Tejada prolonging the inning. Edgin then worked the eighth inning as well, despite Collins saying he needed to be conscious of not overworking Edgin in Byrdak's absence.

FRANKLY SPEAKING: Bobby Parnell began the ninth inning and served up a homer to Chase Headley on the frame's first pitch. Frank Francisco, whom Collins said he planned to use regardless of the game circumstances, began warming as Parnell subsequently surrendered a double and then a walk.

Francisco, in his first game action since landing on the DL on June 24, inherited a four-run lead and two runners from Parnell with one out. He needed two pitches to coax a game-ending double play from John Baker.

WHAT’S NEXT: The Mets already have clinched a winning three-city, 11-game road trip heading into Sunday’s finale, in which Matt Harvey (1-1, 1.59 ERA) opposes Jason Marquis (4-6, 4.08) at 4:05 p.m. ET. After splitting four games in Arizona, the Mets took three of four in San Francisco and have now split the first two games in San Diego. It will be the third start of Harvey’s major league career.