ST. LOUIS -- Cardinals ace Adam Wainwright used Twitter to reassure his fans that he is symptom-free and feeling “great” after he was placed on the injured list on Friday upon testing positive for COVID.

Wainwright, 40, last pitched on Wednesday in Kansas City when he limited the Royals to one hit and one walk over seven innings. There was no designation given to Wainwright’s assignment on the IL, and under MLB protocols, he cannot be activated until he returns two negative COVID tests. Wainwright, who is 3-3 with a 3.18 ERA, is scheduled to make his next start on Tuesday against the Orioles at Busch Stadium.

“Fingers are crossed that he can still make his Tuesday start,” said Cardinals president of baseball operations John Mozeliak before Friday’s game. “He and I were texting this morning, and he feels great.”

“Just so everyone knows, I feel great,” Wainwright posted on his Twitter feed on Friday not long after being placed on the IL. “100%, with zero symptoms. Out of an abundance of caution and following MLB protocols I have to test negative twice before I can return. Which we're hoping is very soon. Thanks for thinking about me!”

The Cardinals, who are in San Francisco for a four-game series against the Giants, earlier this week placed shortstop Edmundo Sosa on the COVID-19 IL, while three medical staffers as well as a clubhouse attendant also tested positive for the virus. Sosa and the staffers were sent back to St. Louis, and replacements traveled to Kansas City and later onto San Francisco with the team.

“Unfortunately, when we were doing all that contact tracing on that original group, [Wainwright] was identified as someone we had to test for,” said Mozeliak. “Even though he was asymptomatic, it still came back positive. So it’s unfortunate, but those are the rules, and we’ll play by them.”

When asked about a potential growing outbreak among the team, Mozeliak did not express immediate concerns but acknowledged a national trend of rising cases.

“I think the reality is that there’s always going to be a concern,” he said. “If you see what’s happening right now in our country, there are other teams that are facing the same issue.”

St. Louis manager Oliver Marmol confirmed the Cardinals aren’t waiting on any further tests.

“[Wainwright] was the one we were waiting on,” he said.

After Sosa returned to St. Louis, rookie Juan Yepez was promoted to St. Louis to replace Sosa on the roster, and he has delivered four hits and his first RBI in his first two MLB games.

Left-hander Steven Matz was activated off the bereavement list to take Wainwright’s place on the active roster. Matz, who signed a $44 million free-agent deal with the Cardinals in the offseason, is 3-1 with a 4.56 ERA after throwing six scoreless innings against the Royals on Monday. Matz is scheduled to pitch in San Francisco against the Giants on Saturday.

Wainwright and catcher Yadier Molina notched their 202nd team victory as a starting battery on Wednesday, tying them with Warren Spahn and Del Crandall for the most wins in MLB history. Their hope was to go for the record on Tuesday at Busch Stadium, but Wainwright’s health status clouds that possibility.

Also, Wainwright and Molina are in pursuit of the MLB record for most starts among a starting battery. Teammates for the past 18 years, Wainwright and Molina have started 310 games together -- good for the third most in MLB history. They need seven more starts together to surpass the Spahn/Crandall duo for second and 15 starts to beat the MLB record of 324 set by Mickey Lolich and Bill Freehan.