Tracy went through agility drills and did some running on the field Wednesday as he continued his rehab from last September's microfracture surgery on his right knee.
Arizona manager Bob Melvin expressed some optimism that Tracy could be back playing by the end of April.
"We've been doing it more frequently," Tracy said of his running drills. "I think that [Melvin's] estimate is a good one -- either then or early May. I'd like to get 30 to 40 at-bats before coming back."
Tracy said the next step would be for him to start running the bases, which he could do in eight to 10 days.
Steve Gilbert is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.