Sabean said Monday that he would characterize the recovery on the slugger's troublesome right knee as having "marked improvement."
Bonds, who has had three operations since Jan. 31, has been sprinting and cutting since last Wednesday, working out at the UCLA track under the direction of renowned Angels orthopedist Dr. Lewis Yocum and physical therapist Clive Brewster.
It is not known how much baseball work -- if any so far -- Bonds has been able to perform. Sabean said that once Bonds successfully completes his physical therapy work in Los Angeles, he would likely rejoin the team in September. However, Sabean isn't sure whether Bonds would be able to play on a daily basis, saying, "don't misconstrue that as jumping on the baseball field."
Sabean receives daily e-mail updates on Bonds and speaks to Yocum or Brewster every couple days.
"Spring training was a long time ago," Sabean said. "He could be starting from ground zero as far as the baseball activities."
Bonds, who turned 41 last month, has 703 home runs, third on the career list behind Babe Ruth (714) and Hank Aaron (755). Carlton Fisk's 53 homers are the most any player has hit after turning 41, and that is exactly the number Bonds needs to break Aaron's record.
Bonds batted .362 last season with 45 homers and 101 RBI and walked a major league-record 232 times en route to his record seventh MVP award.
His most recent operation was May 2 to drain fluid and examine an infection.
Bonds wrote on his Web site last week that he believes he might play in 2005 after all -- taking a slightly more upbeat stance than when he told MLB.com earlier this month that he didn't expect to return.
"It would give a boost to the team and give a snapshot of what might be possible next year," Sabean said. "Whether he plays this year or how much remains to be seen."
Sabean, meanwhile, wouldn't say whether a top offseason priority will be adding another outfielder as a backup plan if Bonds can't play in 2006.
"Obviously we have to address our deficiencies and improve the team as a whole," he said.
Information from The Associated Press was used in this report.