Infielder Nico Hoerner exited Wednesday's loss to the Reds with right oblique tightness, Cubs manager David Ross said postgame.
Hoerner struck out on a check swing in the seventh inning, grimacing and immediately grabbing his right side. He walked back to the Cubs dugout under his own power but soon left down the tunnel.
Hoerner, 24, is hitting .313 with a .389 on-base percentage in 39 games this season. He started at shortstop Wednesday in place of Javy Báez, who was available to pinch hit but out of the lineup for a third straight game due to a bruised left heel.
If Báez and Hoerner remain sidelined Thursday, the Cubs won't have a natural shortstop available. They recently optioned Sergio Alcántara to Triple-A Iowa. Someone like David Bote would have to play shortstop — or Kris Bryant.
Bryant took over for Hoerner at shortstop, his second career appearance there. It was technically Bryant's first appearance at the position since May 31, 2016, although he has plenty of recent experience playing in that area of the diamond.
Bryant is often the lone infielder on the left side of the infield when the Cubs shift.
"I've thought about moving him around the middle of the infield a couple of times, actually — when Nico was [on the injured list], especially," Ross said of Bryant.
"With shifts right now, when he's at third, he moves over to short I would say at least half the time, with all the lefties that we shift. He's in that spot a lot.
"I thought he did a pretty good job."