SAN FRANCISCO -- To hearken a U2 melody, the Giants still haven't found what they're looking for.
Having sought a fleet center fielder with adequate defensive skills, they obtained one Monday night, agreeing with free agent Austin Jackson on a two-year, $6 million deal. Jackson will be flanked by right fielder Andrew McCutchen, another acquisition this offseason, and could share playing time with rookie Steven Duggar.
But the Giants aren't done yet, at least according to members of the team's brain trust, who spoke on a conference call Tuesday. They indicated that the club continues to seek another outfielder to add depth, as well as offensive pop, defensive prowess or both.
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Executive vice president of baseball operations Brian Sabean said that the outfield is "still undergoing a facelift." Of Jackson, who hit .318 in 85 games in a platoon role with Cleveland last year, he said, "Did we get him to be our everyday center fielder? Probably not."
Sabean added, "We don't know exactly what's going to transpire between now and Spring Training."
Pitchers and catchers are due to report to the team's Scottsdale, Ariz., training complex on Feb. 13, followed by position players on Feb. 18.

While praising Jackson, general manager Bobby Evans hinted that he might tweak San Francisco's outfield contingent in the offseason's closing weeks.
"We're aware of what Austin brings to the table, regardless of whether there's an addition from the outside or help coming from the inside," Evans said. "He's going to be able to help us regardless."

Evans acknowledged the Giants' reluctance to exceed the $197 million luxury tax threshold, which would force them to contribute to the competitive balance tax.
"We intend to stay with that target for now, below the threshold," Evans said.
Thus, the Giants are unlikely to pursue skilled yet high-priced free-agent outfielders such as slugger J.D. Martinez or the multitalented Lorenzo Cain.
Yet Evans also sounded willing to shatter that ceiling if it meant bringing aboard a suitably valuable and affordable performer. He stated that avoiding a CBT payment was "not a requirement."
"We're staying active with discussions with our options out there," said Evans.
At the very least, the Giants can envision a roster that includes three key newcomers: Jackson, who can play all three outfield positions and is a candidate to bat leadoff; McCutchen, the 2013 National League MVP; and third baseman Evan Longoria, who figures to join McCutchen and Buster Posey in the middle of the batting order.
After finishing last in the NL West a year ago with a 64-98 record, the Giants could have been expected to make significant changes, particularly in the outfield. According to Statcast™, San Francisco's outfield ranked next-to-last in the Majors with minus-16 Outs Above Average (OAA). Meanwhile, according to FanGraphs, San Francisco also recorded minus-45 Defensive Runs Saved (DRS), worst in the Majors last season. Its minus-11.4 Ultimate Zone Rating (UZR) ranked third-to-last among the 30 teams.
"Any time you can pick up two guys [in Longoria and McCutchen] who are heart-of-the-order guys and good defenders and add another piece like Austin, who's going to help shore up the defense, I couldn't feel better about what's happened this winter as we go to Spring Training," Giants manager Bruce Bochy said.
"And I'll speak for the players. I talked to Buster today. He's pumped. He's excited, as we should be. It's a club that needed some help, and we got it."