The soft-tossing lefty was at his best Friday night, pitching San Francisco back into the NL Championship Series with a 5-0 win over the St. Louis Cardinals that narrowed its deficit to 3-2.
"This is definitely it for me," Zito said. "Coming here, especially doing it in a Giants uniform. A lot of people were saying stuff about A's days. And for me, the most important thing is doing everything for San Francisco right now."
Zito looked like the same guy who won the 2002 AL Cy Young Award with the Athletics. He retired 11 consecutive batters in one stretch while scattering six hits with six strikeouts in 7 2/3 innings.
Giants catcher Buster Posey twice tapped Zito on the chest when he was pulled in the eighth. It was Zito's first postseason win since 2006, shortly before he left the A's and signed a $126 million, seven-year contract with San Francisco.
Zito was left off the postseason roster when the Giants won the 2010 World Series because he had pitched so ineffectively. He started Game 4 of the division series against the Reds earlier in this year's playoffs and lasted only 2 2/3 innings.
"I couldn't be happier for him," manager Bruce Bochy said. "He had it all going. He put on quite a show."
The defending champion Cardinals might have thrown away a chance to clinch a second straight World Series trip. Pitcher Lance Lynn's toss on a possible forceout deflected off the second-base bag, paving the way for the Giants' four-run fourth.
"I don't mind him being aggressive if he's got the play," manager Mike Matheny said. "(Shortstop Pete) Kozma was in the right place; he just made a low throw.
"And to do it over again, I'm sure he'd like to take the easy out at first base," he said.
Pablo Sandoval homered for the second straight night and Zito made an extremely rare offensive contribution with a perfectly executed bunt for an RBI single.
Giants defenders made several nice plays behind Zito, including a juggling catch in right by Hunter Pence and a spectacular sliding stop by second baseman Marco Scutaro to rob pinch-hitter Shane Robinson on consecutive at-bats.
Once again this postseason, the Giants benefited from a big error.
Needing three straight wins at Cincinnati to avoid elimination in the division series, San Francisco began its comeback on a bobble by third baseman Scott Rolen in the 10th inning that gave the Giants the go-ahead run in Game 3.
The Giants improved to 4-2 on the road this postseason and have won Zito's past 13 starts, with the last setback on Aug. 2. They're averaging more than six runs a game during the streak, although the lefty didn't need much help in this one.
Lynn, an 18-game winner his first year in the rotation, failed to make it out of the fourth for the second time in the series.
The Cardinals are seeking consecutive pennants for the first time since 1967-68, and trying to advance for the second year in a row as a wild-card entry. One more win would set up a rematch of the 2006 World Series against the Tigers, which the Cardinals took in five games.
Lynn struck out five of the first 10 batters, sailing through the first three innings with no balls hit out of the infield. His undoing was a wild throw off the second-base bag attempting to get a forceout on a comebacker that paved the way for San Francisco's four-run fourth.
The Giants had runners on first and second with one out when Lynn gloved a tapper by Pence, wheeled and waited a bit while Kozma hustled to second. But Lynn threw a low dart off the bag with the ball bounding into shallow right field and Marco Scutaro scoring without a play from second.
Eighth-place hitter Brandon Crawford singled up the middle with the bases loaded on a full count with two outs as Lynn just missed with a kick save for two more runs. Zito, who has just 30 career hits in 310 at-bats in the regular season with no extra-base hits and nine RBIs, laid down a perfect bunt for a fourth run.
Lynn has allowed four runs both of his NLCS starts, although all four were unearned in Game 5.
Zito's only trouble came in the second when Yadier Molina and David Freese, both swinging on the first pitch, opened the inning with a single and double. Lynn, a career .056 hitter including the postseason, hit into a bases-loaded double play to end the threat.
Lynn was 3 for 50 with 1 RBI, 10 sacrifices and 36 strikeouts during the regular season, going hitless his last 42 at-bats.
Standing room attendance for Game 5 was 47,075, a franchise best for league championship play, topping the previous best in Game 4 by 13. ... Actor Matthew Morrison sang the national anthem. ... Longtime Cardinals broadcaster Mike Shannon bounced a ceremonial first pitch from in front of the mound to Lou Brock, teammates on the last St. Louis team to go to consecutive World Series in 1967 and '68. ... Carlos Beltran has 10 career stolen bases in the postseason. ... Matt Carpenter, who subbed for Beltran in Games 3 and 4, is a career .529 hitter (9 for 17) against the Giants counting the postseason, with a homer and four RBIs. ... Cardinals rookie RHP Trevor Rosenthal struck out four in two scoreless innings. He has fanned 11 in 6 2/3 scoreless innings in the postseason while allowing just one hit.