Tracy Morgan Before 911 Emergency -- Signs of Illness

1/23/2012 8:12 AM PST

Tracy Morgan Before 911 Emergency -- Signs of Illness

Before Tracy Morgan fell unconscious at a Sundance award event last night, the actor hit the red carpet with the co-producers of his new film "Predisposed" -- but something wasn't right.

Tracy looked in good spirits on his way into the Creative Coalition Spotlight Awards -- smiling, chatting -- but for some reason, one of his producers felt the need to constantly reassure the actor under his breath ... saying things like, "I'm right here" ... "We got you."

It's unclear from the footage what was bothering Tracy.

TMZ broke the story ... Tracy fell unconscious later in the evening after delivering a near-incoherent award acceptance speech. He was subsequently rushed to a nearby hospital in an ambulance.

A spokeswoman for Park City Medical Center -- where Tracy is being treated -- claims neither drugs nor alcohol were found in Tracy's system upon medical evaluation.

9:50 AM PT: Tracy just tweeted, claiming the high altitude was responsible for his 911 emergency last night -- "Superman ran into a little kryptonite. The high altitude in Utah shook up this kid from Brooklyn."