Klesko, who played under new Giants manager Bruce Bochy for seven seasons in San Diego, is expected to contend for the first-base job with Rich Aurilia but also to potentially play left field.
"Bringing Ryan on board adds an element of versatility to our ballclub," Sabean said. "We have added an offensive threat that can play a couple of positions."
Klesko, who missed 150 games last year after right shoulder surgery, is hardly unique as a multi-positional threat, as Aurilia has played all four infield spots, Pedro Feliz can switch from third to first and backup Mark Sweeney is also a first sacker and outfielder.
Adding to the mix is young infielder Kevin Frandsen, who can play third, short and second base.
A downfall for the Giants last season was a lack of suitable replacements in case of injuries and days off, but the 2006 lineup gives Bochy plenty of options to keep regulars fresh.
Klesko, who has a .372 career on-base percentage and a .507 slugging mark, says he's fully healthy after dealing with shoulder problems in recent years and eager to bring San Francisco back into divisional contention.
"I told guys early in my comeback if I had setbacks, I would probably hang it up, but I feel good now or I wouldn't be playing," said Klesko. "When I'm healthy, I have power and can get on base. Brian and Boch really want to put a competitive team out there, and I know Boch will get the most out of players."
Bochy said Klesko looked like his old power-hitting self the final two weeks of the 2006 campaign and expects the veteran to contribute on a regular basis in a variety of roles.
"He'll play first and some outfield in left," said Bochy. "He's a proven left-handed power bat that can come off the bench and be a threat. It's a nice luxury to have Ryan and Mark Sweeney for their experience, and when we make double-switches."
Klesko laughed when asked about playing in expansive AT&T Park, where left-handers often have trouble reaching the seats, but he reminded questioners he has played at PETCO Park and feels his bat will still be valuable.
"I'll worry more about getting on base and driving the ball in gaps," said Klesko. "It's a tough ballpark like many of them, but I'm more concerned about winning."
To that end, Sabean notes the Giants are "still in the market, we still have money to spend" on pitching, and while the New York Mets are zeroing in on free agent pitcher Barry Zito, the Giants and Texas Rangers are still in the chase, and a Zito sweepstakes winner may not be decided until January.
Finalization of slugger Barry Bonds' one-year, $16 million contract continues, and Bonds has yet to schedule a physical, usually the last step.