Nico Hoerner and Seiya Suzuki remain day to day with ankle injuries and are out of the Chicago Cubs lineup

PHOENIX — The Chicago Cubs’ middle-infield depth is being tested.

Nico Hoerner is day to day with right ankle soreness after exiting Wednesday’s win in San Diego following a collision with second-base umpire Dan Iassogna in the second inning. Hoerner is still being evaluated after initial imaging Wednesday did not show a fracture.

Seiya Suzuki’s status also remains day to day because of lingering right ankle soreness. The right fielder pinch hit in the ninth inning Tuesday but did not play Wednesday. Suzuki took batting practice Friday. Coming off Thursday’s day off, neither Hoerner nor Suzuki was in the lineup for Friday’s series opener at the Arizona Diamondbacks.

Manager David Ross indicated they were available off the bench, though given Hoerner’s ankle continues to get checked out, he likely won’t be a first option.

Hoerner’s absence thins the Cubs’ middle-infield options. Nick Madrigal went on the injured list Tuesday with a low back strain. Meanwhile, shortstop Andrelton Simmons is not yet ready to join the team from his rehab assignment. He will play nine innings Friday and Saturday at Triple-A Iowa.

Ildemaro Vargas, who struggled defensively when he replaced Hoerner midgame Wednesday, started at shortstop Friday with Jonathan Villar slotted at second base.

“I know each day he feels a little bit better and is trying to listen to his body and we get really good feedback reports,” Ross said of Simmons. “The main thing it’s getting better every single day. He’s a big-leaguer that’s been doing it a long time. He’ll know when he’s ready and he knows where we’re at. We’ll see how things work out today and then go from there.”

Justin Steele’s left thumb felt fine when he threw a bullpen Friday, including with his slider grip, which gave him issues in his last start to cut the outing short from soreness. The Cubs will see how he feels Saturday. Sunday’s starter versus the Diamondbacks hasn’t been determined, but Ross expects it will be either Steele or Wade Miley.

Right-hander Alec Mills (right quadricepts tightness) is scheduled to throw a bullpen Saturday while infielder David Bote (left shoulder surgery) is getting at-bats in extended spring training at the team’s complex in Mesa, Ariz.