DENVER -- After first baseman Brandon Belt opened the season going 1-for-10 with five strikeouts, manager Bruce Bochy gave him a day off in Monday's series opener in Colorado, hoping to give him a chance to clear his head and get back to the groove that found him hitting .378 (28-for-74) with three home runs in the Cactus League.

"He was fighting it a little bit there, so I'm just giving him a couple days with the day off tomorrow," Bochy said.

The move allows Bochy to make the most of his versatile outfield, moving Aubrey Huff to his natural position of first base after the veteran started the first three games in the outfield, and bringing in Gregor Blanco to start in right field, giving the team more speed patrolling Coors Field's expansive outfield acreage.

With the 23-year-old Belt coming off his rookie season, Bochy wanted to make sure he didn't start the season off frustrated from a few tough games.

"That's what's not going to happen -- we're not going to let it happen," Bochy said. "He admitted he was pressing a little bit. He wants to do what he can to help the club. I don't want these guys to think like that three games into the season. We've got the season ahead of us. We had a tough series, but I don't want anybody to put too much pressure on themselves early."

Belt hit .225 with nine homers and 18 RBIs in 63 games with the Giants last year, the sum total of his big league experience. He was the Giants' Opening Day first baseman last year, but had three trips up and down to the Minor Leagues as he struggled at the plate and suffered a hairline fracture in his wrist after being hit by a pitch. He started 19 games at first and 31 in the outfield.

"When a hitter tells me he's pressing, it's probably time to give him a day and let him relax a little bit," Bochy said, taking care not to make too much of the move. "It's natural for a young player. It's early in the season, and they want to get off to a good start. They sometimes lose sight that there's a lot of games in the season. The first week is not going to determine what kind of year you're going to have. It's a natural reaction. I've seen it from a lot of young players."

Though Bochy was unconcerned about Belt's three-day mini-slump, he said he is interested to see how players respond to challenging times.

"You like to watch your players when they're struggling and see how they handle it," Bochy said. "That's what separates your average player from your good players. How they deal with adversity, their mental toughness. That's what you got to have in this game."

Sanchez's first start preview of Posey strategy

DENVER -- It's taken a few days for backup catch Hector Sanchez to try to convert his torrid spring in the Cactus League into big league action, but with Buster Posey taking a day off after catching the first three games of the season, Sanchez made his debut behind the dish in the series opener in Colorado.

"When I came in here this spring, I never thought I could make the team," Sanchez said before Monday's game. "I wanted to show the staff that I'd made my defense better since last year. I didn't come in to make the team. I came in to work hard and learn more. Probably with one week left, I started thinking it was possible in my mind, but I never thought I'd make the team."

Sanchez was penciled in to open the season in Triple-A Fresno, having split most of the 2011 season between Class A San Jose and Fresno. He did play 13 games with the Giants over a couple of big league callups. He was overshadowed in Spring Training by what manager Bruce Bochy consistently called the toughest competition of the spring: the battle for backup backstop between Eli Whiteside and Chris Stewart. But after Sanchez hit .383 with four homers in Arizona and showed improved defensive ability, it was Whiteside and Stewart heading back to the Minors and Sanchez making his first Opening Day roster.

"It was a little bit of a surprise, but I wasn't shocked," Bochy said of Sanchez's spring surge. "I was surprised with him last year. We brought him up, and I thought he did a good job. He had a good year last year, and I heard reports from down in Venezuela [Winter League] that he played very well. So I wasn't really surprised at what he did this spring, but maybe a little bit on the catching side, because he's just gotten better and better."

Though he didn't think it would earn him a spot on the roster so soon, the impression Sanchez made on Bochy and the big league coaching staff is exactly what he hoped for this spring.

"I wanted to practice my defense," Sanchez said. "I tried to watch every pitcher on the team, because we have some of the best pitchers in the league. When I wasn't playing in Spring Training, I'd run to the bullpen and try to watch the guys [throw their bullpen sessions]."

The careful attention to studying his pitchers paid off in his first start Monday, as Sanchez teamed with Barry Zito for a shutout, marking the Giants' first win of the season after being swept in Arizona.

"You have to give Sanchez a lot of credit," Bochy said of the shutout. "A young catcher, he did a great job with [Zito]. The two were in synch and had a good tempo going. He just did a terrific job. We had three tough games [against the D-backs]. It's good for the club to finally get on the board here."

The battery first worked together last June when Zito was in Triple-A Fresno on a rehab assignment and Sanchez had just jumped from Class A to Fresno. Sanchez caught a complete game for Zito that month, and they established a good comfort level.

"He has a good feel," Zito said of Sanchez. "He's not scared to go out there and call a pitch that wouldn't be a normal pitch to throw in the situation. If things get under pressure out there, he's always mellow and relaxed. He has a lot of poise at that position for his age."

Part of what made Sanchez such an appealing backup for Posey is that from an offensive perspective, he gives the Giants the best alternative to Posey among the possible catchers, allowing Bochy to give Posey a full day off when he keeps him out of the starting lineup. The Giants are being cautious with Posey, who is recovering from an injury that broke a bone and ripped the tendons in his lower left leg, ending his season last May.

"Hector's a good hitter from both sides," Bochy said. "He can handle the bat. He showed that last year, both in Fresno and when we called him up. He's got a good idea of what he's doing up there."

Sanchez delivered immediately Monday, knocking a run-scoring single from the left side of the plate in the third inning and singling again from the right side of the plate and coming around to score in the fifth frame.

"One of the reasons Hector's here is he's not a guy you pinch-hit for," Bochy said. "Posey is available to pinch-hit, but unless I have to, I won't put him behind the plate."

After his first start, Sanchez should have a better idea of what he's doing on the big league roster after such an unexpected spring bloom. His 13 games, including six starts, in the Major Leagues last year gave him a taste of belonging, but to open the season on the Giants' roster was an unexpected experience for the 22-year-old switch-hitter. The first three days were a challenge, watching every inning from the bench after being accustomed to playing most days as he quickly worked his way through the Giants' system.

"It's hard, seriously, because you play every day in the Minor Leagues," Sanchez said. "You have to keep working and be ready for the moment. If you don't play every day, you go to the gym, work with the bat, block balls, throw to bases. That's what I've done the last couple days to be ready for this day. Keep working and be ready for the opportunity."