ST. LOUIS -- John Bowker made his Major League debut for the San Francisco Giants less than a week ago. Now, he's already trying out a new position.

The 24-year-old rookie outfielder was in the starting lineup for Friday's game against the St. Louis Cardinals as the Giants' first baseman.

"I'm definitely excited about it," Bowker said before the game.

Giants manager Bruce Bochy had talked to the rookie about the position.

"He got some work in Major League camp and was sent down and got quite a bit of work there with [director of player development] Chicken [Fred] Stanley," Bochy said. "I talked to him. I said, 'Listen, you're gonna play first base. Are you comfortable?' He said, 'Yeah.' I said, 'Let's go ahead and start this now.'"

Bowker is hitting .538 (seven hits in 13 at-bats) with two home runs and seven RBIs in his first four games.

But the left-handed Bowker hasn't played first base regularly since his junior year at Rio Americano High School in Sacramento, Calif. He played outfield as a senior in high school and at Long Beach State.

"I'm looking forward to going out there and getting in a game," Bowker said.

Bochy likes the idea of getting Bowker's bat in the lineup more often.

"It helps us to get him in the lineup the way he's contributing and [keep] the outfield with [Fred] Lewis and [Aaron] Rowand and [Randy] Winn. If this can work, it really would help out quite a bit with the fact that you're going to get him in the lineup as much as you can.

"I understand it's not an easy position to learn right away, but we feel with the work he's had that it's something he can handle."

If he adapts to the new position quickly, Bowker could play his way to a regular position in the lineup. The Giants' other two options at first base, Daniel Ortmeier and Rich Aurilia, are both right-handed hitters.

Bowker has been productive with the bat in his limited time with the Giants.

After hitting .307 with 22 home runs and 90 RBIs a year ago at Double-A Connecticut, Bowker had two hits in each of his first two games, including home runs in both games, against the Cardinals last weekend at AT&T Park.

Bowker became the first Giants player in the club's 126-year history to hit home runs in his first two games in the big leagues and his seven RBIs during those first two games were the most in the Majors by any player since 1954.