Jackson was placed on the 15-day disabled list -- marking his second DL stint of the year -- on July 5 with a right hamstring strain and has been stationed in Arizona since the beginning of the All-Star break. Manager Bob Geren on Tuesday reported that he is "feeling better," but no plans have been made for him to play in Minor League games.
"He's hitting," Geren said, "so he's staying in shape. He's still working on the running, though."
Jackson had hoped to return shortly after the break, but Geren mentioned "there was a plateau" stage -- not necessarily a setback -- in his rehab development.
"He was progressing for a while," Geren said, "and then all of a sudden, he was kind of staying the same. But now he's back on track."
At the time he was placed on the DL, Jackson said he first strained his hamstring on June 17 at Chicago's Wrigley Field while playing his third game with the A's after being traded by the D-backs and aggravated the injury the next day in St. Louis. Jackson missed 18 games for Arizona -- spending time on the DL with a strained right hamstring from April 18 to May 8 -- but he said the injury occurred in a different spot this time.
In Jackson's stead, Geren has been playing musical chairs with his outfield, handing Matt Watson and Matt Carson, along with Gabe Gross, time in the outfield. On Tuesday, with Rajai Davis back in the lineup and playing left field after missing a couple of games with a sore left hamstring, Geren placed Coco Crisp in center and Carson in right field.