New England Patriots tight end Rob Gronkowski will undergo back surgery on Friday and is expected to miss two months, a source told ESPN's Adam Schefter on Thursday.
Gronkowski left Sunday's game against the New York Jets with an injury. A source told Schefter that ultimately Gronkowski was diagnosed with a herniated disk. The need for surgery was first reported by The Buffalo News.
Gronkowski and quarterback Tom Brady were not present for practice on Wednesday. Brady, who is listed as having a knee injury, returned to the field Thursday.
Gronkowski had returned to action Sunday after missing the team's game the week before because of a chest injury.