PHOENIX -- A's closer Grant Balfour threw his fourth bullpen session Saturday since undergoing knee surgery last month while second baseman Jemile Weeks' return to game action could be pushed back to Monday, according to Oakland manager Bob Melvin.
The A's hope Balfour, who saved 24 games for the club last season, will make at least five appearances this spring before heading back to California for Opening Day.
"He's on a good schedule right now," Melvin said. "If he continues at the pace he's on right now and there are no setbacks, he certainly would be ready for the season."
Melvin added he's not sure yet what the next step for Balfour is moving forward, but he would likely need to throw in a simulated game and/or batting practice before making his spring debut.
Meanwhile Weeks, who is recovering from a bruised right shoulder he injured on March 1, participated in all team drills Saturday, but his manager might give him an extra day of rest before reinserting him back into the lineup. Melvin originally said Friday the team targeted Sunday for his return.
"If you're in spring and you get to the point where it's time to play, maybe it's prudent to give him one more day." Melvin said. "We'll see tomorrow, if he's close to 100 percent tomorrow, there's a chance he plays, but if not, maybe we give him one more day."
Weeks was 6-for-11 with five RBI in four spring training games before he suffered the injury.
Tyler Emerick is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.