(CNN) -- Houston Texans head coach Gary Kubiak will remain hospitalized for at least one more day after collapsing as he walked off the field for halftime of the team's Sunday night game against the Indianapolis Colts, the team said Monday. "Gary is alert, coherent and in good spirits," the team said in a statement. "He is continuing to be evaluated and monitored." The Texans didn't elaborate on what might be wrong with Kubiak, who "experienced dizziness and a light-headed feeling" before sinking to the ground, according to the team. On Sunday, defensive coordinator Wade Phillips said the coach "did not have a heart attack, but they're still checking on everything with him."
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Houston Texans coach won't be out of the hospital Monday, team says
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"We were very concerned at halftime," @placeholder tackle Duane Brown said.