ST. LOUIS -- The Cardinals used the utmost of patience and caution with Jack Flaherty's return after 2 1/2 months away from the mound. Now the remainder of his season is uncertain.

The right-hander left his start during Tuesday's 4-3 loss against the Tigers after just two-plus innings (46 pitches, 25 strikes), and exams taken Wednesday morning showed a right shoulder strain, manager Mike Shildt said. Flaherty was placed on the 10-day injured list and will be shut down. With just over a month to go in the season, it’s unclear if Flaherty will be able to return before the close of 2021.

"Fingers crossed that at some point, he can help us this year," said president of baseball operations John Mozeliak, who added that surgery does not appear to be necessary for Flaherty. "But most importantly is making sure he's sound and ready to go for 2022."

In a corresponding move, the Cardinals recalled Junior Fernández from Triple-A Memphis.

Shildt, speaking to reporters before Wednesday’s series finale against the Tigers, had only preliminary results from Flaherty’s scans but said they showed no structural damage.

“Could always be a lot worse,” Shildt said. “Sounds like it's about what we expected and he's going to miss a little bit of time.”

The long-term health of Flaherty will be chief among his outlook for this season. He was out from May 31 into the middle of August with a left oblique strain that included a partial tear. The club has exerted extreme caution on the 25-year-old in his return from that injury. There’s no clear connection between the two ailments, but given the timing of the year, there remains the chance of keeping Flaherty out of action until 2022.

“It's possible, but it's too early to really be able to say with any confidence either way,” said Shildt, who added that Flaherty will need a ramp-up once again if he returns this season.

Flaherty on Tuesday said he was battling what he described as “normal soreness” in the leadup to his start and thought he could pitch through it. But when he was throwing fastballs under 90 mph and allowing back-to-back homers to the middle of the Tigers’ lineup, head trainer Adam Olsen walked up to the mound and then returned to the dugout with the ace, marking Flaherty's second injury-related exit this season.

Flaherty preached confidence to reporters, but he didn’t want to dive deep into the medicals before more information was available.

“I'm just [ticked], I'm just [ticked]. Mentally I'm, you know, I'm just [ticked],” Flaherty said. “Physically, it’s fine, it’s more of a throwing thing than anything. But I’m just [ticked].”

“There's some concern when your ace has to go down again,” Shildt said Tuesday.

Flaherty's night was deflated by consecutive homers allowed to Robbie Grossman and Miguel Cabrera. Flaherty has made a point of fluctuating velocity this season, but each fastball he threw to Grossman was under 90 mph, compared to his season average of 93.7. The slider Cabrera rocketed out was thrown 79.2 mph, compared to his season average of 83.8. A slider one pitch prior was tracked at just 77.5 mph.

Flaherty breezed through the first on 11 pitches, walked three in the second -- including Detroit starter Casey Mize in his first career plate appearance, on four pitches with the bases loaded -- and was then removed after his last pitch resulted in Cabrera’s second-longest homer of the season, 422 feet into Big Mac Land

“It just got less comfortable as the game went on,” Flaherty said, adding that he wouldn’t have started the game if he felt like it was a concern. “Tried to give everything I had and ignore it. ... We got through the first and I was like, ‘All right, I’m good. We can keep it going.’ And just in between [the first and second innings], it stiffened up.”

Flaherty was just three starts returned from a left oblique injury sustained on May 31 which included a partial tear. He was dynamite in his first two starts back, earning a win and a no-decision, and reported to come out healthy in each outing.

Shildt on Wednesday said it’s still too early to tell if Flaherty’s ailments were directly connected, but he couldn’t rule out the possibility on Tuesday.

So where can the Cardinals turn for their rotation? They saw their prime option pitch on Tuesday night, with Kwang Hyun Kim tossing 2 2/3 no-hit innings (working around a pair of walks) in his re-debut out of the bullpen.

Mozeliak believes that "we have innings on this team," which would downplay the possibility of a prospect like Matthew Liberatore debuting in September. Specifically, Mozeliak pointed to Kim swinging back into the rotation as he builds back up from his bout with left elbow inflammation.