Gary Kubiak collapsed as the team left the field at halftime. (David J. Phillip / AP)

Houston Texans Coach Gary Kubiak is in stable condition and will undergo tests today in a Houston hospital after collapsing at halftime of the Texans’ game against the Indianapolis Colts on Sunday night.

(David J. Phillip / AP) (David J. Phillip / AP)

It was a stunning sight to see Kubiak, who is 52 one of the more physically fit coaches in the league, slump to his knees with a grimace. Kubiak was taken off the field on a stretcher and was taken immediately to a hospital. The team said that he did not suffer a heart attack or stroke and never lost consciousness. It was a shock for the “Sunday Night Football” audience and for Texans players. Leading 21-3 at the half, they lost 27-24 with defensive coordinator Wade Phillips stepping in as coach.

“I saw him on the ground and I was asking, ‘What happened?’ ” Phillips said (via the Houston Chronicle). “That’s kind of how it was with everybody, with everybody asking, ‘What happened? What happened? What happened?’

“There was a lot of unknown. … It was a shock to everybody.”

The Texans had a chance to send the game into overtime as the clock ran down, but Randy Bullock’s 55-yard attempt went wide left.  “It was like all the air was taken out of us,” offensive lineman Duane Brown said. “Seeing your coach on the ground is not a sight you expect.”

The Texans now have lost six in a row, although Case Keenum stepped up with 20 of 34 pass completions for 350 yards and three touchdowns.

“Obviously, our thoughts are with our head coach right now,” J.J. Watt said. “That’s a completely different situation, a completely independent situation. That’s a real-life situation right there.”

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