Brian Wilson and the Giants didn't waste much time in having him undergo Tommy John surgery. Dr. James Andrews will handle the operation Thursday in Pensacola, Fla.

Last Thursday, Wilson picked up his one and only save of 2012, at Colorado. On Saturday, the Giants announced that their bearded closer probably needed surgery.

Dr. Ken Akizuki, the Giants' orthopedist, will be on hand for the operation to repair a torn ulnar-collateral ligament. Wilson also had Tommy John surgery while he was at LSU.

"Hopefully all goes well," manager Bruce Bochy said, "and Brian will be pitching next year."

Bochy said Santiago Casilla, who recorded a save in the Giants' 4-2 win Tuesday night, will get "the lion's share" of save opportunities in Wilson's absence.

Zito's the one: The Giants begin a seven-game trip Friday in New York. The opener of a four-game series will be a matchup of left-handers, with Barry Zito going for the Giants and Jonathon Niese for the Mets.

The operative number for Zito in his two starts this season is one. As in, he has issued only one walk in 16 innings.

Lance Iversen/The Chronicle

"I think command comes from confidence," Zito said. "When you have confidence in your stuff, you're not tentative to throw it over the plate, and then command just gets better."

Bochy has paired Zito with catcher Hector Sanchez. Zito, in his 13th big-league season, enjoys working with the rookie.

Said Zito: "It's so easy to label 'me - veteran, him - rookie,' and start building everything off that, but it's not that simple. When you're in the moment, it's a pitcher, a catcher and a hitter, and all the other stuff sometimes just goes by the wayside."

Zito views his two fine outings to open the season as, well, merely two outings.

"That boosts your confidence," Zito said, "but ... you have to stay humble. You have to treat every day like a new experience and a new challenge.

"Tomorrow's not going to be any easier because yesterday was."

Giants on deck Thursday Off Friday at Mets 4:10 p.m. CSN+ Zito (1-0) vs. Niese (2-0) Saturday at Mets 10:10 a.m. CSNBA Vogelsong (0-1) vs. Pelfrey (0-0)