ST. PETERSBURG -- Bottom of the ninth, game on the line and Joe Maddon opened up the cage to release his secret weapon: "Zorilla."

Ben Zobrist, formerly a contact-hitting shortstop of little note, has evolved into an offensive force for the Rays and well worthy of the nickname the manager bestowed upon him that plays off the sci-fi legend, Godzilla. On Thursday afternoon, Zorilla left the cage to pitch hit against Andrew Bailey. And like he has done so much already this season, Zorilla produced magic, sparking a rally that led to the Rays' 6-5 walkoff victory over the A's on Thursday.

Entering the series finale, Zobrist had two pinch-hit home runs this season.

"It's tough to have a good pinch-hit at-bat when you haven't seen the ball a whole lot, especially not at all that day," Zobrist said. "For me, sometimes it's kind of freeing to know that you have one shot -- might as well take your hacks. It's pretty easy to not get a hit in that situation, because it's a tough situation.

"So I kind of tell myself I have nothing to lose. Go up there and look for something hard to hit. And if it's in my zone, try and put a good swing on it. And if it doesn't work out the way you want it to, that's OK, you get another chance tomorrow. I'm just going to make sure I get my hacks in."

And hack he did, swinging at a 1-1 pitch with a man aboard and the Rays trailing, 5-3, to deposit the ball into the right-field stands for a game-tying homer that sparked a three-run ninth inning. Zobrist's heroics couldn't have come at a better time as the Rays closed out an eight-game homestand at a respectable 5-3.

"I'm looking for something hard," Zobrist said. "A fastball or a cut fastball -- and that's exactly what I hit. I hit a cut fastball. He did a good job on the first two [pitches] doing that. And the last one he just left over the middle of the plate."

A Tropicana Field crowd of 14,374 celebrated as Zobrist rounded the bases, pumping his first before touching first at the beginning of his grand tour.

"Isn't it nice to be able to spot [Zobrist] in that particular moment?" Maddon asked. "It's kind of like having a joker in your deck, a card that you can utilize at any time."

Zobrist, who at one time had been a tight ball of nerves when he was the Rays' everyday shortstop at the beginning of 2007, now looks as loose as anybody on the field.

"Absolutely, you have to have fun," Zobrist said. "I think with what we've been able to do, in the Cleveland series and coming in this last game here and coming from behind in the bottom of the ninth. It's so much fun -- you've got to have fun, especially when you're winning and stuff. We were keeping it loose the whole game. Sometimes you feel good, sometimes you feel bad. But, regardless of how you feel, you go up there and you're trying to be aggressive and have a good pinch-hit at-bat."

Dioner Navarro followed Zobrist's homer with a ground-rule double to right off Brad Ziegler. B.J. Upton then drew a walk before Carl Crawford singled up the middle to send home Navarro with the winning run.

"I was just trying to get a pitch to handle, go back up the middle, not try to do too much," Crawford said. "I knew a base hit would win it."

Jason Bartlett had given the Rays a 3-2 lead with a solo home run in the sixth. The Rays took that lead into the eighth, only to see an RBI single by Orlando Cabrera tie the score at 3. Beleaguered closer Troy Percival then entered the game in the top of the ninth and walked two of the first three hitters he faced before Jason Giambi singled off the center-field wall to load the bases.

Joe Nelson took over for Percival and surrendered back-to-back singles, and just like that, the Rays were in their 5-3 hole. But the deficit would only make the comeback even sweeter.

"You had it, you let it slip away and then you bring it on back," Maddon said. "Ben Zobrist has been absolutely phenomenal all year. Just a tremendous at-bat, and then the momentum builds after that and our guys got it done. There is a lot of fight in the group. I love it."

Matt Garza started for the Rays and put forth his fifth successive quality start by holding the A's to two runs on seven hits while striking out eight in 6 2/3 innings, but he wasn't able to pick up his fifth win of the season.

"You have a lead going in [to the ninth], you have a pitcher on the mound that has been exceptional all year and we come out on the short end," A's manager Bob Geren said. "So it's a hard one, but we have played a lot better."