CINCINNATI -- The Reds' already thin rotation will have to plug a hole this weekend after lefty starter Nick Lodolo was placed on the 10-day injured list with a lower right back strain on Thursday. The move is retroactive to Monday.

Lodolo was put on the IL when third baseman Mike Moustakas was activated from it. 

"I think I could pitch with it, it's just a matter of you don't know how you'd react or anything. Or let alone compensate for anything you're not aware of. Just to be safe," said Lodolo, who MLB Pipeline ranks as Cincinnati's No. 2 prospect and No. 41 overall. 

Lodolo, 24, earned his first big league victory during Sunday's 4-1 win over the Cardinals -- the Reds’ most recent win that snapped an 11-game losing streak. He allowed one earned run and five hits with no walks and seven strikeouts. 

As the start went along, Lodolo noticed not everything was right. 

"It was like the third or the fourth [inning]," Lodolo said. "It's not even like low back, it's like almost [an] oblique, but not. It's right behind it. Just something that I went out there and in my warmup pitches, it didn't feel that comfortable. As the game went on, it didn't really feel like it affected me at all. I felt good. It was really more like when I came in and sat down, I felt some discomfort in there."

Lodolo didn't report the issue until Monday. 

"It wasn’t affecting him. The way he threw those last couple of innings, I think that was obvious," Reds manager David Bell said. "He’s fine throwing but based on where it is -- low back -- it’s more of a consideration to [not] force him to compensate in any way for this to lead to anything more serious or another injury.”

Lodolo, who is 1-2 with a 5.52 ERA in his three starts this season, did some light throwing on Thursday morning and had no issues. He is scheduled to throw in the bullpen on Saturday. But the Reds will need a starter that day at Colorado. No. 1 prospect Hunter Greene is slated to start on Friday with Reiver Sanmartin scheduled on Sunday.

One possibility to replace Lodolo is Randy Wynne, who is scheduled to pitch for Triple-A Louisville on Saturday at Columbus. The Reds won't be able to use No. 8 prospect Graham Ashcraft, who is 1-1 with a 1.04 ERA in four starts for Louisville this season, because he just pitched on Tuesday. Wynne is 0-3 with a 4.87 ERA in four starts. 

Cincinnati could also make Saturday a bullpen day. 

“For right now, they all are [options]," Bell said.

The Reds expect to have Lodolo throw in two side bullpen sessions before they would put him back in the rotation.

“The goal would be to have him pitching back here at home that first series," Bell said.

The Reds return home to face the Pirates May 6-8.

"I don't think it's anything big," Lodolo said.