HOUSTON — Joe Martinez staged the Giants’ biggest comeback of the season Wednesday afternoon. His teammates sure knew how to carry on the theme.

In a 10-6 victory over the Houston Astros at Minute Maid Park, the Giants erased a three-run deficit — believe it or not, something they hadn’t done in 107 games this season — to make a winner of Martinez in his emotional return.
Martinez stood tall on a big league mound for the first time since April 9, when a line drive fractured his skull and hospitalized him for a week. With his scars healed and no fear in his eyes, he shut out the Astros in four of his five innings.
As if that wasn’t enough inspiration for one day, the Giants’ graying, 29-year-old backup catcher gave them more. Eli Whiteside waited a long time for his first major league home run but couldn’t have picked a better spot for it — bases loaded with the game tied in the sixth inning.
Whiteside’s previous grand slam made a pinging sound. He couldn’t remember hitting one since he used an aluminum bat at Delta State University in Cleveland, Miss. — a long, long way from the major leagues.
It didn’t seem to matter that the Giants were playing their 20th consecutive game without a day off or that they have struggled to compete on the road. Their bats were light and lively, and for the first time this season, they are 12 games over .500.
They derived their energy from Martinez, a pitcher only hard-core fans could have identified in spring training but who soon earned the devotion of a city. The quiet but tough 26-year-old received stacks of letters and cards from well-wishers after Milwaukee’s Mike Cameron hit the line drive that struck his forehead at AT&T Park.
“I’m just an average-looking guy with an average build,” Martinez said, shrugging. “But I had people coming up to me a lot, especially when I still had the black eye. You don’t want to be known for getting hit by a line drive, but the support I received from everybody, family and friends, it helped me get through.”
Martinez, making his first major league start, did not field anything up the middle and didn’t hesitate to finish his pitches. His only problem came in the second inning, when he couldn’t get his sinker to bite. The Astros scored three runs on four hits, although the Giants infield let him down when Jason Michaels scored from second base on an infield single.
But Martinez made an adjustment, and once again, credit Whiteside with an assist. He and pitching coach Dave Righetti swooped in with some advice.
“I was just jumping a little bit from the stretch,” Martinez said. “They told me to stay back and gather a bit. That helped me fall off a little better.”
In every other game this season, a governor’s pardon wouldn’t have saved the Giants with a 3-0 deficit. But Pablo Sandoval and Freddy Sanchez each had three hits and the Giants tied it in the sixth on Ryan Garko’s RBI single.
They hadn’t erased a three-run deficit in any game, win or loss, since Sept. 20 at Dodger Stadium.
Aaron Rowand followed Garko’s hit with a double and Edgar Renteria was walked intentionally to load the bases with one out. With Whiteside up, manager Bruce Bochy admitted he thought about sending up Bengie Molina.
“If it’s the eighth, I might have made a move there,” Bochy said. “But yeah, it certainly was talked about. Sometimes it’s the moves you don’t make.”
Whiteside became the first Giant to hit a slam for his first major league homer since Brian Dallimore in 2004.
Whiteside was an unexpected hero. Every winning season seems to include a few of those — and one more key ingredient, too.
“You’ve got to have comebacks,” Bochy said. “You’ve got to win a few late in the ballgame.”