[Updated 10:49 p.m.]
Anthony Rendon has been diagnosed with an oblique strain after meeting with Nationals orthopedist Dr. Wiemi Douoguih on Monday, an injury that will end his minor league rehab assignment on terms that are anything but ideal.
The 24 year old came to Washington on Monday after sitting out of games with the Double-A Harrisburg Senators in consecutive days, complaining of tightness in his side. Now he will remain with the team and wait until he can resume baseball activities.
"We're gonna have to slow his progress down a little bit," Nationals manager Matt Williams said.
"He'll stay here until he's ready to play... so we're going to have to sit him a little bit longer and make sure it's okay before he resumes activity. It's just not getting loose for him. So there's a little strain in there and we've gotta take care of it and knock that out before he gets back at it."
Williams compared Rendon's injury to the oblique strain Yunel Escobar had in spring training. Escobar was shut down for 10 days before he started practicing again. Rendon is likely to miss at least several weeks as he goes through the process of resting and then working his way back to game action.
"We've gotta make sure we tae care of it. We'll get a test on it. We'll look at it," Williams said. "We'll have to see how Anthony reacts. There's no timetable on it until we fully assess it."
Rendon missed the last two games on his rehab assignment with the oblique injury after working nearly two months to return from a sprained left MCL. He originally hurt his knee on March 9 while playing defense in a spring training game. He then received several opinions on the injury, including one from Dr. James Andrews.
Rendon began his rehab assignment on April 24 and played two games with Harrisburg before taking a day off. He was then scratched on April 26 when he felt discomfort in his knee. The next day he missed another game with what was revealed as side tightness.
Rendon returned to Harrisburg's lineup on Friday and played five innings. He then missed both games over the weekend due to his oblique.
Rendon, 24, finished fifth in NL MVP voting in 2014 after hitting .287 with 21 home runs, 83 RBI, 111 runs and 17 stolen bases.