SAN FRANCISCO -- On a day when Pablo Sandoval homered and singled in another run, the San Francisco slugger revealed he hardly feels comfortable in the batter's box.

Not after missing 13 spring training games with an irritated nerve in his elbow. Not the way he is missing fastballs he typically would drive into the gap for doubles.

Last year's World Series MVP still wound up with a pair of hits and RBIs in the Giants' 6-3 loss to the St. Louis Cardinals on Saturday.

"You want me to tell you the truth? A little bit lost," Sandoval said about his swing. "A little bit, yeah. I'm trying to get to the point where I was in spring training. Hanging in there and keep working hard."

As Sandoval takes on what has become a very public battle with his weight, he insists he is doing everything he can to get in tip-top shape. Meanwhile, he's certainly showing he has plenty of range at third base.

But he is ready to put all the chatter about his belt size to rest.

For now, he is focused on finding his timing and continuing to play nearly spot-on, hustle defense.

"When I feel good I think I don't miss those pitches," Sandoval said.

The two-time All-Star is hitting .278 with two home runs and four RBIs through five games this season. He had a run-scoring single in the third inning Saturday, then a solo homer to start the eighth. Hunter Pence also homered, with a solo shot leading off the second against Shelby Miller (1-0).

That wasn't enough on a day when Ryan Vogelsong (0-1) struggled to consistently command the strike zone, and Carlos Beltran drove in three runs against his former club to spoil Buster Posey's MVP party a day after Barry Zito and the bullpen three-hit St. Louis.

"We're not quite clicking offensively, but we stayed in the game and had a good couple chances there," Giants manager Bruce Bochy said. "You always go with the history and track record of these guys. They're getting into the flow of things. You look around the league and there's some hitters that have gotten off to somewhat of a slow start."

Posey received his NL MVP plaque in another highlight-filled pregame ceremony, and the Giants will have yet another day of celebrating before Sunday's game with the World Series ring presentation.

Posey also was honored for his batting title and Silver Slugger award. Kevin Mitchell, the 1989 NL MVP, and 2000 MVP Jeff Kent took part, along with former MVP winners and Hall of Famers Willie Mays and Willie McCovey.

"It was definitely a different pregame for me than normal but it was nice to be able to celebrate that with the fans," Posey said.

After spending the spring working on his defense, Kung Fu Panda made several nice plays behind Zito to back the win Friday in San Francisco's home opener - including running down a foul popup near the home bullpen. He did more of the same with his glove Saturday.

Sandoval realizes people will talk about his weight no matter what. It seems to be a nonstop topic lately.

"I feel great," he said before the game, referring to his health. "I'm just concentrating on playing my game and to play baseball. If it all goes well, I'll lose weight. For now, I'm just going to concentrate out there. I know my manager is worried about that because he wants me to be a better baseball player. I know all the people say things about my weight because they want me to be the best."

Sandoval, who hit three home runs in Game 1 of the Giants' four-game World Series sweep against the Tigers last season, had a stomach bug early in spring training and missed those 13 games late in the exhibition schedule that limited his fitness and baseball activities.

"He's a little heavier than he should be at this point but he's getting close to where he should be," Bochy said at the start of the series.

Bochy said he left Sandoval in for the entire game Friday because of his strong defense, which included a couple of diving stops on hard grounders.

"He's been playing so well at third base, so I let him stay out there," Bochy said Saturday. "I like the way he's moving out there. That will play a part in it, how well he's playing defensively, which he's doing a great job."

Bochy still plans to insert Joaquin Arias at third as a late-inning replacement on occasion to both give Sandoval a break and keep Arias sharp and involved. As a pinch-hitter Saturday, Arias lined into a double play on the first pitch he saw from Randy Choate to end the sixth with runners on first and second.

While Saturday was the weekly player weigh-in day, Sandoval sees no need in discussing it.

He will let his defense and bat speak for him.

The 26-year-old Sandoval, listed by the team at 242 pounds, batted .369 in the postseason last year with five doubles, six homers and 13 RBIs. That came after he was benched for four of the five games during the 2010 World Series, when he hit .176 with two RBIs.

During the regular season, he had a .283 batting average with 12 homers and 63 RBIs while limited to 108 games because of a strained left hamstring and a hamate bone fracture in his left hand that required surgery.

Sandoval is taking as much pride in his play at third.

"It's one of those things I concentrated on all spring, working on my defense," he said. "It's great. I was ready for the season. I know that I lost two weeks. It's one of those things, I was working out with the trainer and strength and conditioning to do the full work. I wanted to make sure when I came back to play I was ready to play."

The scrutiny regarding his girth likely won't go away anytime soon, and Sandoval knows it.

"That's just part of it," he said.

• Read more articles by JANIE McCAULEY

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