SCOTTSDALE, Ariz. -- Aaron Heilman continued his quest to win a rotation spot with 5 1/3 innings of work Tuesday afternoon against the Indians.

The right-hander, who has not started a Major League game since 2005, is battling with Joe Saunders and Armando Galarraga for the final two spots in the rotation. He allowed four runs on five hits Tuesday, while walking two and fanning five.

"I was throwing a lot of balls for strikes, getting ahead of hitters for the most part, keeping the ball down," Heilman said. "I made a few mistakes, but other than that I felt good."

Said D-backs manager Kirk Gibson: "He pitched good until he got tired and started missing location in the fifth inning and got himself in trouble, got a couple of balls up."

Heilman has a 5.24 ERA in six starts this spring. He said he thought his chances of winning a rotation spot were still good.

"There have been a few games where I haven't thrown the ball where I wanted to, but I felt like I've made some improvement, made some adjustments," he said. "I feel like I'm able to command the ball in the zone and go out there and give us a chance to win."

Saunders not guaranteed spot in rotation

SCOTTSDALE, Ariz. -- Joe Saunders has two more scheduled starts this spring, and it looks like they could decide whether or not the lefty is in the rotation come Opening Day.

D-backs manager Kirk Gibson named Barry Enright to the starting five on Tuesday, and Gibson made it clear that the rotation only has three confirmed starters right now.

"Right now, I have Kennedy, Hudson and Enright," Gibson said.

As for Saunders, who many penciled in as the Opening Day starter, he is left battling Aaron Heilman and Armando Galarraga for the two final spots. Heilman allowed four runs in 5 1/3 innings on Tuesday against the Indians.

Saunders' status seemed to be news to him -- he has used his outings this spring to work on a cut fastball.

"It is what it is," Saunders said. "If [Gibson] hasn't announced me as a starter yet, he hasn't announced me as a starter yet. It is what it is. I'm not going to make anything more of it than it is."

Saunders will, however, approach the final two starts before Opening Day differently.

"I'm not going to go out there and experiment maybe like I did the first few starts," he said. "Maybe more go out there and just -- you always want to try to get outs. You never want to give up runs, obviously. It's a fact of going out there and being ready to throw -- getting guys out, putting quick innings together, getting your pitch count up and getting ready for the season."

Whether that's as a starter or reliever remains to be seen.