SAN FRANCISCO -- As he strode to the plate with runners at first and second and none out in the 12th inning, Hector Sanchez stared at Giants third-base coach Tim Flannery, fulling expecting to get the sign to bunt.Instead, Sanchez was given the green light to hit away."I was like, 'Wow,'" Sanchez said in Spanish. "That gave me confidence, you know?"If you didn't know, now you do. As do the Houston Astros. Sanchez's single off second baseman Jose Altuve allowed Pablo Sandoval to score from second base and give the Giants not only a 3-2 victory, but reclaim first place in the National League West by 12 a game over the Los Angeles Dodgers.Of course, Sanchez and his career-high fourth hit of the night -- he said he last had four hits in a game in 2010 for Class A Augusta -- had a back story. One of redemption.It was his throwing error on a potential game-ending strikeout with two out in the ninth inning that allowed the Astros to tie the score at 2-2 when the ball scooted away from Sanchez toward the third-base dugout and deny Tim Lincecum just his second win since April 28."That's a tough play to make anyways," said Lincecum, who had a season-high 11 strikeouts in a season best-tying eight innings. He also lowered his career ERA against the Astros to 0.99 and has received two runs or fewer of support in 12 of his 19 starts this season."It was good to see him come up big there."In fact, Sanchez, who was four-for-six with a run-scoring double in the sixth inning, said he was trying to make that last play to clinch the victory for Lincecum, who he caught for the fifth consecutive start."I was too quick on that play," Sanchez said. "The catcher was running. I went too fast."The play also gave closer Santiago Casilla a blown save -- his fourth blown save in his last six opportunities -- as it was his third strike to Chris Snyder that got away from Sanchez, who slid to retrieve the ball and fired to first, wide and late. An alert Justin Maxwell, meanwhile, kept on running from second to score the tying run."That's a tough way to get a blown save," said Giants manager Bruce Bochy."(But) it is rewarding to see a guy who felt so awful a few innings earlier come through."It was the rookie Sanchez's second walk-off hit of the season, along with the game-ending base hit he had on May 6 in the 11th inning against Milwaukee."It's what we want to do," Sanchez said, "keep winning, keep playing."And, it turns out, keep getting the green light.