Fowler was reinstated from the disabled list, where he spent the last couple weeks recovering from a bruised right knee. He was injured when his foul ball struck his knee during an extra-inning victory against the San Francisco Giants on Aug. 24.
Shortstop Troy Tulowitzki and third baseman Ian Stewart could return in the next couple days. Both tweaked their backs Monday against Cincinnati and have missed the past two games. Tulowitzki leads the team with 24 homers and Stewart is next with 23 on the year.
"They're both coming along very, very nicely," manager Jim Tracy said before the Rockies hosted the Reds on Wednesday night. "We'll see where we're at, but there is the possibility we could have both of those guys back [Thursday]."
Also, right-hander Aaron Cook, on the 15-day disabled list, threw off the slope of the mound in another step toward returning from a shoulder strain that has sidelined him since mid-August. However, it's too soon to determine when he'll be back.
The same goes for reliever Huston Street, who hasn't pitched in the last week due to biceps tendinitis. He played catch Tuesday but there's still no firm timetable for his return.
"He's feeling better, and we're just going to continue with the program they have mapped out for him," Tracy said. "We have made a little bit of progress and some headway with him."
Right-hander Ubaldo Jimenez, who tweaked his right hamstring during a six-inning outing on Monday, was scheduled to throw a bullpen session on Thursday. Based on how that goes, the Rockies will determine whether Jimenez should go forward with his next scheduled start Saturday at San Diego.
"He's doing throwing," Tracy said. "Obviously, we have to keep a very close eye on that leg but he is trying to move forward. He's actually a lot further along than I thought he would be at this point in time."