ST. LOUIS -- Carlos Martínez's return to the rotation this season was rocky, both on and off the field. He suffered the final blow in Wednesday's 12-3 loss to the Royals, when he allowed eight runs on nine hits in five-plus innings.

The Cardinals placed the right-hander on the 10-day injured list on Thursday with a left oblique strain, which effectively ended his season -- even if the Cards play into October.

“Even if we make that deep run, it’s not likely,” Cards manager Mike Shildt said. “I’ll never say never. But clearly, it’s impactful for him the next several weeks. We’re not anticipating he’ll be able to do a lot of anything. So you look at the schedule, and it’s very unfavorable to think about a return.”

Martínez made five starts this season and failed to really gain traction in any of them. One was before he tested positive for COVID-19, and four were after he returned. He missed more than a month while battling the virus, with symptoms severe enough that sent him to the hospital three or four times for IV treatments.

Martínez earned a spot back in the rotation after a healthy offseason and Spring Training that showed the Cardinals his shoulder was strong enough to maintain a starter’s workload. But he finished this season 0-3 with a 9.90 ERA across 20 innings. The Cardinals won one of his five starts.

“A lot of high hopes, put a lot of time and energy into it,” Shildt said. “Had a really good spring, a lot of positive stuff. Just couldn’t get off on the right foot. And you don’t want to minimize the fact, nor make an excuse, but this guy was affected by COVID probably more than anybody in this league. And at one point was just concerned about his own well-being and livelihood. … People wonder why his stuff wasn’t the same -- who knows? Could be a contributing factor. The guy was hooked to IVs for multiple days.”

What’s next for Martínez is unknown. He’ll rehab the oblique and enter the offseason facing uncertainty. The Cardinals could look to move the 29-year-old this winter.

In a corresponding move Thursday, the Cardinals recalled right-hander Johan Oviedo, who will be available out of the bullpen this weekend against the Brewers. But the Cardinals will likely hope they don’t need him in long relief because they’ll need at least one starter if they play a doubleheader in Detroit on Monday. Those one or two makeup games would only be played to determine if a team gets into the playoffs, or if the Cardinals could become the home team in a Wild Card Series as a top-four seed.

“He’d be a candidate,” Shildt said. “I’d like to have a crystal ball to see how five games are going to play out in four days.”

And the Cardinals do still have a shot at the National League Central title. The first-place Cubs lost to the Pirates on Thursday, putting them three games ahead of the Cards and Reds, who are tied for second place entering Thursday night. The Reds have the day off before playing the Twins for three games this weekend. The Cubs play three games against the White Sox this weekend.

St. Louis on Thursday opened a five-game series over four days against the Brewers, who are one game behind the Cardinals and Reds.

If the postseason fields are set and playing in Detroit would only impact seeding, but not home-field advantage, then the makeup games would not be played.

The most direct route for the Cards to get to the postseason is to take three of five against the Brewers and root for the Twins to take two of three against the Reds this weekend. If the Cardinals and Reds end the season tied for second place, the tiebreaker would go to the Cardinals, who hold a 6-4 season record over Cincinnati.

In other words, the race has come down to this weekend.