PITTSBURGH -- Antonio Brown, the Pittsburgh Steelers All-Pro wide receiver, suffered a partially torn calf muscle in Sunday's 27-24 loss to the New England Patriots, a source told ESPN's Adam Schefter.
Brown is unlikely to play next week but is expected back for the postseason, the source said.
Brown left Sunday's game early in the second quarter with a left calf injury and did not return. Team officials helped Brown off the field and to a blue tent on the sideline. He was then taken to the hospital for evaluation.
Brown attempted to catch a pass in the end zone when a Patriots defensive back appeared to roll over his left leg.
Brown is considered one of the Steelers' toughest players. He hasn't missed a regular season game because of injury since 2012.
Earlier in the game, Brown became the first receiver in NFL history with five consecutive seasons with triple-digit receptions, breaking his tie with Marvin Harrison at four.
Brown entered the Week 15 matchup with the Patriots with 99 catches.
Brown has elevated himself into the MVP conversation with 101 catches, 1,533 yards and nine touchdowns, including several plays that clinched last-minute victories.
"[Brown] deserves to be an MVP candidate, if not the MVP," quarterback Ben Roethlisberger said during the week. "The first WR to get it, I don't know anyone more deserving. What he's capable to do every week is spectacular. I'm happy to be a part of it and do my little part. It's so much fun to watch him."
Steelers coach Mike Tomlin announced that rookie running back James Conner suffered an MCL injury against the Patriots.