CHICAGO -- D-backs left-hander Robbie Ray, who suffered a concussion when he was struck in the head by a line drive last Friday, has returned to Phoenix to be examined by Dr. Javier Cardenas.

"Ray came in [Tuesday], he was on the bicycle, it was the first bit of activity that he's done," D-backs manager Torey Lovullo said. "He felt good. There continues to be a decrease in the symptoms, which is a very good thing. Obviously, the next step, as we move forward, will be to be told by those doctors what we should be doing. Everything that has happened is exactly the way it was mapped out."

One thing that appears certain is Ray will not start Friday in San Francisco when the D-backs next need a starter. Ray's turn in the rotation would have been Thursday, but with Monday's day off, the team was able to slide Zack Greinke up from Friday.

Taijuan Walker will start Saturday and Patrick Corbin will get the nod Sunday.

As for who will start Friday, Triple-A Reno lefty Anthony Banda appears to be the leading candidate, given that he has not pitched since last Thursday and is not scheduled to start for Reno.

"We'll have an announcement here very shortly," Lovullo said, when asked about Banda.

Getting work in

With the D-backs en route to a 16-4 loss to the Cubs on Tuesday, Lovullo was looking for something that he could do that would help his team going forward.

With that in mind, catcher Chris Iannetta got an inning of work in at third base.

"There have been times where we were out of infielders, and maybe the next step would be to insert a catcher in the game," Lovullo said. "I've talked to him and Jeff Mathis about potentially playing somewhere on the field. Chris said he's played third before. I just wanted to see what he looked like out there."

Iannetta has appeared at third base four times in his big league career.

"If it ever comes up, I'd be more than happy to do it," Iannetta said. "It's fun to get over there and be a kid again and just play baseball. In no way, shape or form is catching a job, but getting out of that, you just go back to being a kid and playing wherever on the field you can."

Thrilled

Infielder Jack Reinheimer made his big league debut in the fourth inning Wednesday night as a pinch-hitter and struck out.

"It's quite the adrenaline rush, for sure," Reinheimer said. "It's kind of tough to settle yourself down. I was a little bit done. But it was fun, that's what baseball is all about."

Reinheimer made his first big league start Wednesday, playing shortstop and batting eighth.