Tyler Chatwood spiked a pitch in the third inning of Sunday afternoon's 10-1 win over the Reds, and he immediately motioned to the Cubs' dugout at Great American Ball Park. The pitcher then walked off with an injury, dealing another setback to Chicago's staff.

Chatwood's issue was described as right elbow discomfort by the Cubs -- this after the right-hander was making his second start since returning from an injured-list stint due to a mid-back strain. He will be further evaluated on Monday's off-day.

“We'll get him looked at when we get back home,” Cubs manager David Ross said.

Ross added that Chatwood said he felt something after throwing a first-pitch breaking ball to Joey Votto in the third inning. It was the next pitch -- a changeup in the dirt -- that prompted the pitcher to call for the medical staff.

Righty Colin Rea finished the third inning for Chatwood, and then Ross summoned José Quintana from the bullpen. Over the next three innings, the lefty limited the Reds to one solo homer by Votto in the sixth, finishing with six strikeouts and one walk in the effort.

“When I saw him running back to the dugout, I said, 'What happened?'” Quintana said. “I know how hard he's been working and how he prepared for this start, you know? I heard it was his elbow. Hopefully he's going to be back soon. Hopefully it's not a bad injury.”

Both Chatwood and Quintana (left thumb) came back from the 10-day IL on Tuesday, with the righty getting the start that night against the Tigers. Chatwood lasted a dozen batters in the outing in Detroit, ending with more walks (five) than strikeouts (two) in 1 1/3 innings. Quintana followed Chatwood out of the bullpen with three solid innings on Tuesday as well.

In five starts this season, Chatwood has posted a 5.30 ERA in 18 2/3 innings, in which he has 25 strikeouts against nine walks. Ten of the 11 runs he has allowed on the season came in the two starts (Aug. 6 and Tuesday) on either side of his stay on the IL.

Against the Reds, Chatwood worked 2 1/3 innings with a pair of singles surrendered. With a runner on second in the third, he sent an 85-mph bouncing at the edge of the grass in front of home plate before calling for the Cubs' head athletic trainer.

An off-day on Monday helps give the Cubs time to map out the next week for the rotation. The Chatwood injury will likely come into play on Saturday, when Chicago hosts the Cardinals in a doubleheader. Quintana would now seem a safe bet to slide back into the rotation at that point.

“That's why it's so hard to plan sometimes,” Ross said. “I want to give you guys everything you want to know, but it really is a wait-and-see and assess as we go. And it was so nice to have Q back there on the back end of that and that we could stretch him out a little bit more.”

Quintana said he feels ready to rejoin the rotation, if asked.

“I feel great,” he said. “I don’t know what’s coming for me the next time I take the mound. But I feel great and I felt really sharp today. All my stuff was good. … I feel ready to be back in whatever spot I can help my team.”