SAN FRANCISCO — The Barry Bonds era in San Francisco is probably headed into its final months.

Bonds knows it. The Giants know it. And everybody involved is determined to make a playoff push in what is likely the last run for this club with the star slugger, not to mention a handful of other key players.

Bonds, who turns 42 on July 24, realizes he might not be back with the Giants for a 15th season — prepared to take his talents to the American League as a designated hitter if he returns at all in 2007.

Bonds has said he would like to return next year for a 22nd major league season if his health allows, though lately he has sounded more uncertain.

“I don’t know yet, I have no idea,” Bonds said. “My thing about next year is my kids, that’s it. My son’s a junior in high school. He’s going to be a senior. I want to be with my son, my kids.”

Bonds hit 12 home runs in the first half to give him 720 for his career, 35 from tying home run king Hank Aaron’s all-time record of 755. He passed Babe Ruth and moved into second place on the all-time list with No. 715 on May 28.

Bonds doesn’t have a total he believes he must reach by the end of this season to give himself a realistic shot at Hammerin’ Hank.

“None. I’m capable of that,” he said of hitting 35 home runs in one season at his age. “I’m not predicting.”

Bonds has played in 69 of San Francisco’s first 89 games, batting .249 (47-for-189) with 39 RBIs, 74 walks and 29 strikeouts. The sharp drop in production from Bonds’ MVP seasons in 2001-2004 can be heavily attributed to his age and the effects of missing all but 14 games last season following three operations on his troublesome right knee.

Bonds has also had a difficult year off the field. A federal grand jury is investigating whether the slugger perjured himself when he testified in 2003 in the Bay Area Laboratory Co-Operative steroid distribution case that he had never knowingly used performance-enhancing drugs.

And just last week, Bonds’ personal trainer, Greg Anderson, was sent back to prison for refusing to testify against Bonds. Anderson previously served three months in prison after pleading guilty last year for his role in the BALCO scandal.

But Bonds has always been able to keep his legal problems from distracting him once he’s at the ballpark and expects to play better after the break.

“It’s going to get better. I’m not worried about it,” he said. “It ain’t the end (of the season). I don’t try to fix something that really isn’t broken.”

Bonds missed the All-Star game for just the second time as a Giant when he has been healthy. He said there was no reason for a farewell selection in Pittsburgh, the city where he began his career.

“Say goodbye to Barry? You think I’m leaving?” he said. “It can’t be goodbye to Barry yet until Barry wants to say goodbye.”

There are questions surrounding several of his teammates, too: ace Jason Schmidt, right fielder Moises Alou, outfielder Steve Finley, second baseman Ray Durham, third baseman Pedro Feliz, lefty reliever Steve Kline, right-handed starter Jamey Wright and infielder Jose Vizcaino all can become free agents at the end of the season.

Manager Felipe Alou also is in the final year of his contract and isn’t sure whether he will be back.

“I think it’s fair to say with free agents, we’re going to go through a huge transformation,” general manager Brian Sabean said. “It’s going to be a huge makeover. ... I don’t know if you say the last hurrah, but you can do the math. I can see us getting younger and attacking the market as aggressively as we can. The one thing we can hang our hat on is our young pitching.”

For now, Sabean wants to win the NL West and is looking to add a bat to upgrade the lineup, like the Giants did with the acquisition of Randy Winn from Seattle at the trading deadline last year. Unless the Giants — who are 31/2 games back of first-place San Diego — fall completely out of contention, Sabean doesn’t see himself dealing any top players such as Schmidt.

“I don’t see ourselves being out of the division race,” Sabean said, then noted, “We’re trying to win the division. We’re probably going to have to tweak things to do so.”