ST. LOUIS -- Jeremy Hefner, who rehabbed his way back from two right elbow procedures to latch on with the Cardinals' organization this year, is likely to be out until at least August after an MRI revealed right shoulder inflammation.
Hefner revealed the news via a Wednesday evening tweet in which he described having felt some discomfort in his pitching shoulder during his last two starts. He is scheduled to receive a cortisone injection on Thursday morning and then begin a rehab process that is expected to take six to eight weeks.
In his tweet, Hefner described the diagnosis as "not the best news, but definitely not the worst news." Cardinals general manager John Mozeliak confirmed the news.

Hefner went through a grueling rehab process to even get back on a baseball mound this season. He underwent Tommy John surgery in late 2013, and then found out he needed it again just 14 innings into his rehab work in 2014. That second procedure cost Hefner the entire 2015 season.
The Cardinals took a chance on him anyway and signed Hefner to a Minor League contract over the winter. He performed well in spring and has been a part of the Triple-A Memphis rotation since the start of the season. Hefner had a 3.50 ERA through his first eight starts before allowing six earned runs in each of his last two outings. Hefner lasted 1 2/3 innings in his start on Sunday.
His absence will further thin the Cardinals' starting pitching depth. The organization previously lost Marco Gonzales for the season due to elbow surgery, and Tim Cooney has yet to throw a pitch this year because of left shoulder troubles.
Hefner made 50 Major League appearances with the Mets in 2012-13 before being sidelined by injury.