And they probably won't stop there in their efforts to upgrade their offense.

Jeff Lane, Renteria's agent, confirmed Wednesday night that he had just returned from San Francisco, where he negotiated with Giants officials.

"We're very close to a deal," said Lane, who declined further comment.

The Giants have not made any comment regarding a potential deal with Renteria.

Renteria batted .270 last season with Detroit, his lowest average since he hit .260 with St. Louis in 2001. He also totaled 10 home runs and 55 RBIs in 138 games for the Tigers. That would still represent an upgrade for the Giants, whose shortstops ranked last in the NL in batting average (.228) and OPS (.576) and tied for last in home runs (one) and runs (51).

The Giants hope that Renteria can regain the form he displayed in 12 National League seasons before joining Detroit. He's a career .290 hitter, a five-time All-Star and a two-time Gold Glove winner.

Renteria became a more viable commodity Monday, when Detroit refused to offer him salary arbitration. As a result, the Giants won't have to give Detroit their second-round selection in next June's First-Year Player Draft as compensation for signing Renteria.

During a conference call to announce the signing of right-hander Bobby Howry, Giants general manager Brian Sabean acknowledged that the club might make another free-agent move this week. Sabean added, "If that comes about, it'll enable us to be creative in other areas."

That could mean a trade. Yahoo.com reported that the Giants had discussed dealing left-hander Jonathan Sanchez to the Florida Marlins for third baseman Jorge Cantu, who hit .277 with 29 home runs and 95 RBIs last season. Or the Giants could stick with free agency, where sluggers such as Adam Dunn and Pat Burrell are available. But insiders believe that the Giants rate both as only secondary options.

The Giants also are believed to remain definite contenders for the services of left-hander CC Sabathia, one of this offseason's top free-agent prizes. But Sabathia is still considering other options, mostly notably the New York Yankees' reported six-year, $140 million offer.

Logic would dictate that if the Giants continue to eye Sabathia seriously, they easily could shift attention to left fielder Manny Ramirez and first baseman Mark Teixeira, the other two premier free agents. But although the Giants have talked with agent Scott Boras, who represents both Ramirez and Teixeira, speculation has not linked the club to either player.