SAN FRANCISCO In perhaps the most important game for both clubs so far in 2012, a pair of Cy Young Award winners were set to duel in the rubber match of the Giants-Dodgers series, as the longtime rivals battle for the NL West Division crown.One of them, Barry Zito, resembled the hurler that took home pitchings most prestigious honor in 2002. The other, 2011 winner Clayton Kershaw, never made it out of the training room.Zito was brilliant in 6.1 shutout innings while Kershaw was a late scratch with a sore hip as the Giants took the game and the series with a 4-0 win over Los Angeles on Sunday evening in front of a sellout crowd and national television audience. They lead the Dodgers by five and a half games with just 22 left to play after winning two of three this weekend.Hunter Pences two-out, two-run double in the first inning set the tone, while Angel Pagan and Buster Posey provided key hits in the middle innings, including Poseys 20th home run of the season. But it was Zitos performance that trumped all else.I thought he did a nice job of throwing the ball to both sides of the plate. His curveball was great, he was able to throw it backdoor to righties, and back foot, said Posey, who caught Zito for the second time in his last four starts. Overall, it seemed like he pitched with a lot of confidence. He did a great job.Sergio Romo, who closed out the game, said: He aint backing down from those guys, and he aint backing down from anybody, so he came out today ready to rock. Thats just the attitude we all have. We understand and honestly believe were pretty dang good. Were just going to go out and play and do that, and Barry is a great example of that attitude.Zito surrendered a double to Mark Ellis to start the game, but after getting out of that inning unscathed, settled in nicely. He scattered four hits and walked three while striking out four, and was never really in trouble until he allowed two baserunners with one out in the top of the seventh.When Bruce Bochy called upon Santiago Casilla, the AT&T Park crowd showed its appreciation for Zitos performance with a standing ovation.That was nice. The crowd was electric tonight, and very involved, said Zito, who secured his 11th win against eight losses. Every pitch in the game, we just have the best atmosphere in baseball here.Zito was also grateful for Casilla, who struck out pinch hitter Bobby Abreu and later got Shane Victorino to fly out to left with the bases loaded to end the seventh.The bullpen has just been outstanding, he said. Casilla came in and really slammed the door there with one out and two runners on against the heart of the lineup. For Bochy to manage the bullpen the way he has, he doesnt get enough credit. Its not easy in the first place.While no one would admit that Kershaws absence was a relief, the Giants were surely fortunate to face righty Joe Blanton rather than the Dodgers ace. Kershaw was 5-0 against the Giants last season, and while hes just 1-3 against them this year, still sports a miniscule 1.74 ERA in 31 innings pitched against San Francisco in 2012.Hes one of the best pitchers in the game. We havent done a lot with him, Bochy said. We have found ways to get wins against him, but thats because the guy pitching for us has done a great job in the game hes pitched. We still had our work cut out, Blantons a good pitcher. Hes been around and knows what hes doing, and sure, when you dodge Kershaw you dont mind, but at the same time they have a lot of depth out there. We went into this game knowing we still had work to do.Pence is plenty familiar with Blanton, as the two started the season on the Philadelphia Phillies roster before they were dealt to the West Coast. His clutch first inning hit, after Posey had struck out, was clearly the biggest offensive moment in the game.When youre facing Joe, I knew he was going to probably come in with some fastballs, and he has a good cutter and good slider, Pence said. Thats what I was getting ready for.Bochy said: Especially once they got Buster there, its about picking each other up, and Pence came through with that double. To get an early lead, thats what youre always hoping for. Those two-out hits are what win ball games for you. He came through there, and I think it helps guys relax.While a five-and-a-half game lead with less than a month to go in the season could be viewed as insurmountable, the Giants arent acting like theyve accomplished anything just yet.This was a big series, Posey said. I thought we came out and played well. Today was a huge game. Again, you cant say enough about the performance Zito had. We do have a decent amount of baseball left to play, so we have to keep going and keep pushing.Zito said: We certainly cant rest on our laurels. We have to fight every day, and thats something weve been doing in spite of people weve been losing with injuries and other things. We cant take anything for granted.