The cause of Roethlisberger's ailment and potential impact have yet to be determined.
Steelers' quarterback Ben Roethlisberger is in concussion protocol after leaving practice early on Tuesday when he suffered an apparent head injury.
Coach Mike Tomlin issued a statement through Burt Luaten, the Steelers director of communications.
"Ben Roethlisberger sustained a hit today in practice. He is being evaluated by team doctors as part of the concussion protocol."
Per multiple reports, Roethlisberger fell to the ground after throwing a pass on the final play of a "Seven Shots" team period. He was on the ground holding his head for a few minutes prior to being helped up by teammates.
He then managed to walk off the practice field under his own power alongside Pittsburgh general manager Kevin Colbert and head trainer John Norwig.
Scary moment in Steelers practice during 7 shots. Ben Roethlisberger goes down after throwing a pass. Stays down for a few minutes as entire team gathers around. Not hit. Seems to be ok— Ed Bouchette (@EdBouchette) August 14, 2018
Ben chatting with head trainer John Norwig, GM Kevin Colbert and others moments before he walks off the practice field, his day over after Seven Shots. No limp— but at one point grabbing his head and lying on the ground for several moments pic.twitter.com/sjrq0NyCpF— Chris Adamski (@C_AdamskiTrib) August 14, 2018
Roethlisberger just left the field with trainers. He appeared to fall on his head from the pocket so he could be getting a concussion evaluation.— Jeremy Fowler (@JFowlerESPN) August 14, 2018
The 36-year-old is regarded as one of the most durable signal-callers in the NFL. Through 14 seasons, he has suffered three concussions (October 2006, November 2009 and November 2015). In October 2016, Roethlisberger suffered a torn meniscus, but only missed one game following surgery. He started 15 games last season but sat out the Steelers' season finale against the Browns.
Roethlisberger did not appear in Pittsburgh's lone preseason game against the Eagles last week.