CINCINNATI -- Nationals starting pitcher Joe Ross will undergo Tommy John surgery Wednesday morning, manager Dusty Baker announced Saturday.
Ross, 24, was placed on the disabled list Friday after exiting his July 9 start with discomfort in his right shoulder. He had both an MRI and MRI arthrogram to determine the severeness of the injury, which ended up being a full thickness tear of his right ulnar collateral ligament.
The surgery will be done by Dr. Keith Meister in Texas. His timetable for return beyond this season is still in question.
"He's going to have surgery this week," Nationals general manager Mike Rizzo said. "We'll take it from there."

For now, Ross' spot in the rotation will be filled in by Jacob Turner, who is currently with Triple-A Syracuse. Turner has pitched in 18 games this season for the Nationals but has started just two. He is 2-3 with a 5.08 ERA this season. He will start Tuesday as the Nationals take on the Angels.
Ross was 5-3 this season with a 5.01 ERA, but tallied four straight quality starts before his appearance on July 9 against the Braves. This will be the first surgery of his career, and Baker said Ross is taking the news about as well as he could.
"I told him that he had to go in with a positive outlook," Baker said. "And your first one is always tough. I've had a number of them. And you have to be proactive vs. reactive, and you have to go into things with a positive outlook on things. And I told him to talk to a couple guys here that have had this procedure before, which helps, mainly Matt Wieters and Stephen Strasburg. So it's always tough on the first one, but I know a whole bunch of guys that have come back better and have thrown harder and came back with better mechanics than when they left."