Two NFL head coaches are undergoing treatment after being hospitalized this past weekend.

Houston Texans head coach Gary Kubiak had to leave Sunday night’s game against the Indianapolis Colts after collapsing on the sidelines. He was immediately taken off the field on a stretcher and sent to a hospital, where he remains as of late Monday morning. Kubiak was conscious the entire time and did not suffer a heart attack or stroke, according to the Houston Chronicle.

"He had an episode; he was light-headed and dizzy," Houston general manager Rick Smith told NBC. "He was evaluated by a number of specialists … he is awake and coherent.”

While Kubiak may not have suffered a stroke, he has been treated for “stroke-like symptoms.” Sources tell ESPN’s Adam Schefter that the 52-year-old was given IV medicine that is used to break up blood clots in stroke victims. Kubiak will undergo further tests to determine exactly why he collapsed.

The Denver Broncos also saw their coach hospitalized this past week. While the team was off with a bye, John Fox was taken to the hospital on Saturday after becoming dizzy and suffering chest pains. He is scheduled to have heart surgery on Tuesday. Fox did not suffer a heart attack, as initially suspected.

The surgery will keep Fox off the sidelines for a while. He’s expected to miss four-to-six weeks after he undergoes aortic valve replacement surgery. The 58-year-old will be replaced by defensive coordinator Jack Del Rio, who has been named the interim head coach.

''I sincerely appreciate all of the support from friends, Denver Broncos fans and so many around the league today,'' Fox said on Saturday night. ''Although I am disappointed I must take some time away from the team to attend to this pre-existing health condition, I understand that it's the right thing to do. I have great confidence in our coaches and players, who are fully committed to our goals."

On Sunday, Fox spoke with several Broncos players. Special teams captain David Bruton told USA Today that the coach sounded like he was in good spirits.