The Cardinals expect to get the results of an MRI on Alex Reyes' right elbow on Wednesday, which could indicate he needs Tommy John surgery. (File)

By Rob Rains

 UPDATE - General Manager John Mozeliak announced Wednesday morning that Alex Reyes needs Tommy John surgery and will miss the 2017 season. An MRI on Tuesday revealed that Reyes, one of the top pitching prospects in baseball, has a torn ligament in his right elbow.

Original story from Tuesday:

The next 24 hours figure to be an anxious time for the Cardinals.

The team began spring training workouts on Tuesday in Jupiter, Fla., without rookie pitcher Alex Reyes, who missed a scheduled bullpen session and then was sent for an MRI on his right elbow.

Before undergoing his regular physical exam, as did the team’s other pitchers and catchers on Tuesday morning, Reyes alerted the Cardinals’ training staff that he was feeling discomfort.

General Manager John Mozeliak told reporters in Jupiter the team expects to learn the results of the MRI on Wednesday.

Potentially, the news could be that Reyes will need Tommy John surgery, which would knock him out for all of this season and perhaps the early portion of 2018 as well.

A source told ESPN.com’s Jim Bowden that Reyes does have a torn ulnar collateral ligament but that Reyes was seeking a second opinion. There was no independent confirmation of that report.

Mozeliak is well aware of that possibility, but he said he would not speculate on the seriousness of Reyes’ elbow injury, preferring to wait for the MRI results.

"Let's wait for tomorrow and react then," said Mozeliak. “We're obviously hoping for the best.”

The 22-year-old Reyes, the Cardinals’ best pitching prospect, came into camp as one of the favorites for the National League Rookie of the Year award after his strong showing at the end of last season.

After being called up in August, Reyes was 4-1 with a 1.57 ERA in 12 games, including five starts. He struck out 52 batters in 46 innings, four innings under the limit to be able to retain his rookie status heading into this season.

The Cardinals had not determined if Reyes would open the year as a starter or in the bullpen, trying to save some innings on his arm. If he is not able to pitch, it likely will lead the way for Michael Wacha to return to the rotation, assuming he is healthy.

If Reyes does have to miss this season, he would be the fourth Cardinals pitcher in the last seven years to miss a year because of Tommy John surgery. Adam Wainwright missed all of 2011, Jason Motte all of 2013 and Lance Lynn all of last year.

At the very least Reyes is now unlikely to pitch for the team from the Dominican Republic in the World Baseball Classic next month. He had been named to a list along with several other pitchers who could have been added to the team if it advanced past the first round of the tournament.