Though Cody Ross took a step in his rehab of a calf injury Tuesday, the Diamondbacks outfielder will likely open the season on the disabled list, D-backs manager Kirk Gibson confirmed.

"I'd rather (do that) than him push it and injure himself for six to eight weeks," Gibson said. "Let's get it right. If we have to DL him to do that, then it's certainly he an option."

An MRI on March 4 revealed a strained soleus muscle in Ross's left calf. The D-backs shut him down from any running for two weeks before letting him start working on a weight-bearing treadmill. Ross progressed slowly, Gibson said, and it has become increasingly apparent he would not be ready to play on Opening Day.

Ross could progress this week to a point where he feels capable of starting the season on the big league roster, but the D-backs are choosing to err on the side of caution. With projected center fielder Adam Eaton out six to eight weeks with a sprained left ulnar collateral ligament, the D-backs don't want to risk losing another outfielder.

On Tuesday, Ross jogged on the ground under head athletic trainer Ken Crenshaw's supervision for the first time since the injury was diagnosed. Ross said he'll take Wednesday off from any running and pick it up again Thursday, hopefully pushing himself a little more.

"It was just basically a tester, a feeler just to make sure I didn't feel it," Ross said. "I didn't feel it once. That's good mentally, good physically. It was definitely nice to get out there and jog a little bit."

Gibson said if Ross does start on the disabled list A.J. Pollock will start the season in the majors, possibly in a starting role alonsgside Jason Kubel and Gerardo Parra. Gibson also said Tony Campana and minor leaguer Alfredo Marte are candidates for a fourth outfielder job. Campana has been limited by a cut on his left hand.