SAN FRANCISCO (Reuters) - Pitcher Barry Zito has been both brilliant and awful during his career, been the toast of the town and nearly run out of it.

Lauded as nearly unhittable when winning the Cy Young Award in 2002 with Oakland, Zito's $126 million switch to San Francisco looked like a massive mistake as he struggled to find top form and was even subjected to jeers from Giants fans.

However, Zito has picked the perfect time to resurrect his career.

With San Francisco down 3-1 and facing elimination in the best-of-seven National League Championship Series on Friday, Zito pitched masterfully, allowing the Giants to blank the St. Louis Cardinals 5-0 and ultimately reach the World Series.

Zito, with a 1.74 ERA in two postseason starts, is once again a crowd favorite and will get the chance to erase many of the bad memories on Wednesday when he opens the World Series for the Giants against the Detroit Tigers at AT&T Park.

"For him to keep grinding, as we say, and trying to get better, for him to be at this point and starting the first game, I was really glad," Giants manager Bruce Bochy said on Tuesday.

"I told him, 'I'm glad to hand you the ball on the first game.' With all he's been through and the way he's handled it, it's been off the chart."

Zito was almost unhittable in 2002 when he went 23-5 with a 2.75 earned run average for the Oakland A's. He was a three-times All Star before signing the big-money, seven-year deal after the 2006 season to play for the Giants.

PRIDE, HONOR

However, the left-hander never reached .500 with San Francisco until this season, playing so poorly that he was left off the postseason roster in 2010 when the Giants won the World Series.

Giants fans, at times, were merciless.

"I feel like I've grown up in this game," Zito told reporters. "When I came up in Oakland, I felt like I was a boy in the game. You have talent, and you just keep going to the next level, and all of a sudden everyone is kind of like looking at you.

"There are fans chanting your name and stuff, and you're not really sure why. And then to mature in this game is a big deal.

"That process is in huge part becoming a free agent, going to a new team, signing a big deal and dealing with everything that comes with that."

Zito went 15-8 with a 4.15 ERA in 32 starts this season, going 7-0 in his last 11 outings. With four-times All Star Tim Lincecum struggling, his timing could not have been better.

Bochy said the southpaw was "ecstatic" to learn he would start the Fall Classic.

"He was proud, honored that we have the trust in him to start Game One," said the manager.

Zito tried to be calm but was clearly excited to take the mound just two years after sitting at home watching his team mates win the World Series.

Barry Zito has matured.

"I feel like an adult in the game now," he said with a smile.