Alex Reyes (elbow) will require Tommy John surgery.
According to Jim Bowden of ESPN.com, Alex Reyes has a partial tear of the ulnar collateral ligament in his elbow and will go for a second opinion.
According to Jeff Passan of Yahoo Sports, "there is significant concern" with the Cardinals that Alex Reyes needs Tommy John surgery.
Alex Reyes underwent an MRI on his pitching arm on Tuesday morning.
Alex Reyes skipped a throwing session Tuesday at Cardinals' camp.
Craig Mish of SiriusXM reports that Alex Reyes has committed to pitch for the Dominican Republic in the World Baseball Classic.
Cardinals GM John Mozeliak indicated Wednesday that he will not trade Alex Reyes.
Alex Reyes held the Reds to a lone run over six innings of work, striking out six, in a no-decision Thursday.
Alex Reyes earned his fourth victory of the season on Saturday, limiting the Cubs to three runs on six hits over his five frames.
Alex Reyes fired seven innings of shutout ball Sunday in the Cardinals' 3-0 blanking of the Giants.
Alex Reyes will start for the Cardinals on Sunday against the Giants.
Alex Reyes pitched 4 1/3 scoreless innings in relief Tuesday against the Cubs to earn his second win of the season.
Alex Reyes is being moved back to the bullpen.
Alex Reyes gave up two runs over six innings in a no-decision against the Reds on Friday.