SCOTTSDALE, Ariz. -- Zack Greinke and Robbie Ray will both start Sunday afternoon as the D-backs have split-squad games against the White Sox and Rangers.

Which of them will be on the mound March 28 when the D-backs open the regular season at Dodger Stadium? That’s still to be determined.

“We feel like we have a couple of really good candidates, and we just want to hit it right,” D-backs manager Torey Lovullo said. “We want to make sure whoever gets that nod is going to give us the best chance to win the game. It’s a tremendous honor, so it’s something that we’re going to pay close attention to.”

Greinke would seem to be the natural choice given that he’s coming off a season in which he was 15-11 with a 3.21 ERA in 33 starts. The right-hander has also had a good spring, saying he feels healthier than he has in years.

Ray, though, has also had a good spring, and he seemed to hit his stride down the stretch last year after missing two months with an oblique strain.

“We probably haven’t gotten to the point where we’ve had conversations with either guy, and I want to just see some things through their eyes and get some information from there,” Lovullo said. “What they think and what they say matters to me, and I haven’t yet had certain conversations that I want to get down to.”

Lovullo named Greinke his Opening Day starter early in camp in 2017, his first year at the helm, but waited until later last year before giving the nod to left-hander Patrick Corbin.

Greinke last year battled a variety of ailments during the spring and wound up starting the third game of the Regular Season.

Koch making case
Aside from a three-batter stretch in the fourth inning, right-hander Matt Koch turned in another sharp outing in Saturday's 7-1 loss to the Cubs as he continued his battle to win a spot in the bullpen.

Koch allowed four runs -- three of which came when he allowed the first three hitters of the fourth to reach -- over five innings.

“I’m feeling good,” Koch said. “I feel like the ball is coming out well, everything is coming together. Just have to make some tweaks here and there and everything will be a lot better.”

Back-field action
D-backs outfielder Adam Jones, who signed a free-agent contract Monday, was scheduled to take some more at-bats in a back-field game Saturday after doing so for the first time Friday. Jones is expected to play in the field for the first time Sunday in a back-field game.

Injured outfielder Jarrod Dyson (strained left oblique) hit and played in the back-field game. The team still hopes that he will be ready come Opening Day.

Regulars David Peralta, Jake Lamb and Nick Ahmed also played in the back-field game in order to get as many at-bats as possible.

Up next
Greinke will face the White Sox at Salt River Fields on Sunday, while Ray gets the ball against the Rangers in Surprise, Ariz. Archie Bradley, who is competing with Greg Holland for the closer’s role, is also slated to pitch against the White Sox, as is Yoan Lopez.