SCOTTSDALE, Ariz. -- Edgar Renteria made his first impressive appearance for the Giants without even stepping onto the diamond.

As Renteria tried on a pair of uniform pants Tuesday, a reporter asked him about the weight he lost this offseason, which was reportedly at least 10 pounds. Renteria tugged at the waist of his pants, showed off the two to three inches of excess room and prompted laughter by saying, "You can tell."

Though Renteria no longer needs an elastic waistband, it's not a stretch to say that the 33-year-old shortstop looms as one of the Giants' most crucial performers this season. Should Renteria approach the form that made him a five-time All-Star, three-time Silver Slugger recipient and two-time Gold Glove winner, the Giants' climb toward respectability will become much easier. If Renteria relives the struggles he endured through much of last season with the Detroit Tigers, the two-year, $18.5 million contract he received as a free agent could be remembered as yet another Giants boondoggle. Previous entries include the George Foster, Gaylord Perry and Joe Nathan/Francisco Liriano trades, the Armando Benitez signing and the construction of Candlestick Park.

Renteria's physical condition as Giants position players reported to camp offered early hope, since his subpar 2008 was attributed to his thickened build. A .291 career hitter entering the season who batted .332 with Atlanta in 2007, Renteria slumped to .270 with Detroit. Worse, observers generally agreed that he had lost a step or two defensively.

Detroit manager Jim Leyland delivered an unblinking yet hopeful appraisal of Renteria during the Winter Meetings.

"I think he probably didn't come in [to Spring Training] as prepared as he needed to be," said Leyland, whose 1997 World Series-winning team in Florida included Renteria. "I think as the year went on, he realized that, and I think that will be taken care of. ... He didn't knock in as many big, big runs [55] as he did in the past, but he's still capable of doing that."

Forced to work himself into playing shape during the regular season, Renteria hit .296 after the All-Star break. He intends to sustain that level this year.

"I think I can still play," Renteria said. "I always say that if one day I wake up and I feel like I can't play anymore, I'll quit, no matter how much money I'm making."

Said Giants manager Bruce Bochy, who studied videotape of Renteria, "I don't have any concerns with him."

Returning to the National League also could help Renteria, a .293 hitter in 10 NL seasons compared with .274 in two American League campaigns.

"I think that makes a big difference for a hitter when you know the league and the pitchers," Renteria said. "They have a saying in baseball, 'See the ball.' If you know the pitcher, that's better for you."

Leyland, who partially blamed himself for Renteria's apparent slothfulness last year -- "I think maybe I didn't stay on top of him coming in" -- offered a rosy prediction: "I think he'll be a very good player for the Giants."

Renteria doesn't have to be super. Just solid. He's projected to bat second, where he can employ his hit-and-run skills.

"I've been playing against him for years, and there's probably nobody better in the game at hitting behind runners," fellow infielder Rich Aurilia said.

Renteria might lack the defensive wizardry of Omar Vizquel, who occupied shortstop for the previous four seasons, but as with any infielder, nobody will complain if he consistently makes the routine plays.

The competition at second base among Kevin Frandsen, Emmanuel Burriss and Eugenio Velez could complicate Renteria's adjustment to the Giants, since he might not know who his double-play partner is until the end of March. Renteria flashed dry humor as he remarked, "That's OK. It's better than not having anybody, right?"

"He's a consummate professional," Aurilia said. "He has a lot of hardware collected, between Gold Gloves and Silver Sluggers. To bring someone in like that in the middle infield as a stabilizing force is going to be important for this team, especially if there's a lot of young guys surrounding him."