SAN FRANCISCO The Giants were held hitless for six innings between the first and eighth, but broke a 2-2 tie in the ninth on Brandon Crawfords line-drive single to center for their sixth walk-off win of the season.Starting pitching report: Madison Bumgarner started and ended a 1-2-3 first inning with strikeouts, then watched as his offense staked him to a 2-0 lead. But Bumgarner gave it right back in an ugly second inning that included two doubles and a bloop hit from San Diegos starter Edinson Volquez.After his 26-pitch second inning, Bumgarner benefited from a spectacular double play in the third, then worked around a leadoff double with two strikeouts for a scoreless fourth.Bumgarner kept the Padres off the board in the fifth and sixth innings as well, but racked up 100 total pitches in the process, putting him on a short leash entering the seventh.The Giants 22-year-old leftys best inning was his last, as he cruised through the seventh with two strikeouts and a slick fielding job on a comebacker to end the inning.Despite the quality start, Bumgarner actually raised his home ERA this season from 1.81 to 1.90.Bumgarners final line: 7 IP, 6 H, 2 ER, 2 BB, 9 K (111 pitches, 69 for strikes)Bullpen report: Sergio Romo entered a tie game in the eighth inning and wouldve been on the hook for a loss if not for Angel Pagans spectacular catch and throw double play to end the inning.Santiago Casilla got the call in the ninth and issued a one-out walk to former Giant Jesus Guzman. But the fill-in closer got Everth Cabrera to strike out to end the inning At the plate: The Giants wasted no time getting on the board, just as they did in Mondays 7-1 win. It wasnt a four-run first inning like in the series opener, but the Giants managed two runs to give Madison Bumgarner an early cushion.Nate Schierholtz, leading off for a fourth straight game, roped a double into the rightfield corner, advanced to third on Ryan Theriots infield single, and scored on a Melky Cabrera groundout. Pablo Sandoval just missed a home run with a deep drive into triples alley. Though he only ended up on second, it was more than enough to bring in Theriot for a 2-0 lead.After the Padres tied the game, the Giants went down in order in the second and wasted back-to-back leadoff walks in the third thanks to back-to-back strikeouts from Buster Posey and Brandon Belt.In the fourth through seventh innings, the Giants mustered just one walk and struck out six times against Edinson Volquez. When Luke Gregerson entered the game in relief of Volquez in the eighth, the Giants struck out two more times before collecting their first hit since the first inning, an infield single from Cabrera. He was stranded, though, when Buster Posey grounded into a fielders choice.Belt led off the ninth with a full-count walk against Joe Thatcher and advanced to second when Angel Pagan poked a ball through the hole between shortstop and third. With Brandon Crawford attempting to lay down a bunt, both runners advanced on a passed ball, changing Crawfords approach at the plate. Crawford came through with a clean line-drive single back up the middle to score Belt and end the game in style.In the field: Ryan Theriot, Brandon Crawford and Pablo Sandoval teamed up for a very high-degree-of-difficulty double play to end the top of the third inning. Theriot fielded Carlos Quentins sharp ground ball while on his knees, then fed Brandon Crawford, who leaped to avoid the baserunner and get off a throw. Crawfords relay was low, but Sandoval dug it out while stretching to do the splits. Unfortunately, the highlight-reel play cost Sandoval, as he left the game immediately after with a left hamstring injury.With the go-ahead run at first, Angel Pagan brought back memories of Gregor Blancos catch in Matt Cains perfect game when he covered a lot of ground in the left-centerfield gap and dove to make an amazing grab to rob Carlos Quentin. Pagan wasnt done yet, as he threw the ball back toward the infield as his momentum carried him closer to the outfield wall. Brandon Crawford caught Pagans throw and relayed the ball to Brandon Belt at first to complete the rare 8-6-3 double play.On the bases:In the third inning, Nate Schierholtz and Melky Cabrera contributed their third and eleventh stolen bases of the season, respectively. Neither came around to score, though.Attendance: The Giants announced their 131st consecutive sellout crowd with a paid attendance of 42,559.Up next: The Giants will go for the three-game sweep in a Wednesday matinee game at 12:45 p.m. The Padres will start right-hander Jason Marquis (3-5, 3.79 ERA) to oppose fellow right-hander Tim Lincecum (4-10, 5.72 ERA). Lincecum dominated the Padres on April 28, allowing just an unearned run in eight innings; hes also 10-4 with a 2.03 ERA against San Diego in his career. Your current Jeopardy! champion, Insider Andrew Baggarly, will be back on the beat for the series finale.