Foltynewicz will undergo further evaluation over the next couple of days and could be released from the hospital Thursday. Once released, he will be on blood thinners for at least six weeks.
The Braves said it is too early to know when Foltynewicz will be cleared to resume physical activities during the offseason.
Foltynewicz felt some discomfort Thursday and was rushed to the emergency room when he arrived at Turner Field on Friday with redness and swelling around his right arm. He remained at Piedmont Hospital until Monday, when he was transferred to undergo the surgical procedure at the Kennestone Hospital.
Now that the procedure has been completed, the Braves believe the blood clots might have been related to the bout of pneumonia that has sidelined Foltynewicz since he was unable to make his scheduled start Sept. 2.
Foltynewicz was one of the three prospects the Braves acquired when they sent Evan Gattis to the Astros in January. He made his Atlanta debut May 1 and spent the next six weeks posting a 5.19 ERA over nine starts.
After spending most of the next six weeks with Triple-A Gwinnett, Foltynewicz returned to Atlanta's rotation and produced a 6.47 ERA over six starts. He said that he started to battle some fatigue and congestion around Aug. 16. But he was not diagnosed with pneumonia until the first week of September.
Though Foltynewicz was not going to have enough time to build his endurance to be used as a starter again this season, the Braves had been planning to bring him out of their bullpen over the next couple of weeks.
Mark Bowman is a reporter for MLB.com. Listen to his podcast. This story was not subject to the approval of Major League Baseball or its clubs.