ST. LOUIS -- You can push them, you can corner them, and you can force them to pitch Barry Zito to stave off elimination.

But you can't kill the Giants, at least not yet.

Really, the worse it gets for them, and the lower they fall, the better the Giants get.

And the more you doubt Zito in a pressure-cooker game, the stronger he gets.

The most stunning development of all: After his sublime Game 5 performance, Zito is now a symbol of this team's passion, pride and perseverance.

Barry Zito: Standard-bearer and season-saver. Of course he is!

"This guy, he is some kind of tough," manager Bruce Bochy said of Zito after the Giants' 5-0 victory over St. Louis on Friday.

Simply put, Zito was astonishing in Game 5; while rarely exceeding 85 mph, he pitched 72/3 scoreless innings, almost single-handedly staving off elimination and extending this NLCS to Game 6 on Sunday at AT&T Park.

The Giants still trail in this series 3-2 and need many more brilliant performances to survive. St. Louis also is an incredibly tough-minded team, with a host of comebacks in its recent history, too.

So this series is bound to bounce back and forth, from guts to glory on a rotating basis. It's just who these teams are.

But at this point, you can only acknowledge the Giants' ability to summon their best at the darkest hours.

Quick summary: The Giants dropped the first two games at home to Cincinnati in the NLDS only to win the last three in Cincinnati.

And ... here they go again, maybe.

"It's tough to say exactly what it is -- we enjoy playing the games," said outfielder Hunter Pence, who gave another pregame speech to rally the troops Friday.

"Wish we didn't wait that long."

Stat of the year: The Giants are 1-5 when not facing elimination, but they're 4-0 in this playoff season when facing elimination.

On Friday, the Giants and Zito held on when the Cardinals threatened in the first and second innings.

Then the Giants broke through against Cardinals starter Lance Lynn in the fourth -- scoring four unearned runs after Lynn botched a comebacker.

As a capper, the fourth run scored on Zito's first career bunt single.

From there, Zito went into total cruise control, and the Cardinals seemed flustered by the development.

But I guess it shouldn't be that surprising -- the Giants have won 13 consecutive games started by Zito, an almost incomprehensible stat given that Zito has thrown in several clunkers over the period.

"Zito, he has been phenomenal for a long time," Pence said. "I feel like we've won every single time ...

"You feed off it. He has this really intense focus. When you see him working that hard, it kind of gets everyone locked in together."

That's the 2012 playoff Giants: They don't give in, they don't give up, and they don't give away anything when their playoff lives are at stake.

Basically, whatever doesn't eliminate the Giants only makes them stronger.

"Everyone counted us out four or five times this year already," said scheduled Game 6 starter Ryan Vogelsong.

"First, when (Brian) Wilson went down, people said we couldn't do it. Then we lost (Melky) Cabrera, unfortunately, people said we couldn't do it.

"The Dodgers made the big trade, people said we weren't going to do it. We go down two (games) to Cincinnati, they said we're not going to do it.

"I think it's the perseverance through the whole season is where we draw the confidence that it's not over until the last out is made."

Again: Can anybody count them out again? Not I. Not anybody who has seen this playoff run from day to day and shout to shout.

Only 11 of 76 teams that trailed 3-1 have come back to win a seven-game series in major league history.

But the Giants sure plan to make it 12 of 77, and now they're coming home for another last stand.

In the NLDS, the emotional jump-start came from Pence's pregame speech before Game 3 -- and the Giants never lost after that.

In the NLCS, the Giants' emotion focused on Zito, who has been so often beleaguered and battered in his time with the Giants after signing a $126 million deal.

They are circling the wagons. They are proudly showing the chips on their shoulders. They are almost impossible to kill off, and growing prouder and prouder about that.

They can throw Barry Zito at you, and if it's with the season on the line, the Giants and Zito just cannot be defeated right now.

Read Tim Kawakami's Talking Points blog at blogs.mercurynews.com/kawakami. Contact him at tkawakami@mercurynews.com.