COLUMBIA, Mo. -- Missouri linebacker Aaron O'Neal died Tuesday after collapsing during a voluntary workout with teammates, a hospital official said.
University Hospital spokeswoman Mary Jenkins confirmed the death of O'Neal, a 19-year-old redshirt freshman from the St. Louis suburb of Creve Coeur.
The cause of death was not immediately available.
"I can't begin to express how deeply saddened we are by this loss," coach Gary Pinkel, who was out of town Tuesday, said in a statement. "Aaron was a quality young man who was well-liked and respected by his teammates and coaches.
"We are all very shocked and hurt right now, but the most important thing we can do is to focus on Aaron's family and to assist them any way we can."
The Columbia Daily Tribune reported on its Web site Tuesday night that O'Neal started to struggle with conditioning drills about 45 minutes into the hourlong workout at Faurot Field, the Tigers' home stadium. Temperatures at the time were in the mid-80s.
At the end of the workout conducted by strength and conditioning director Pat Ivey, O'Neal lay on the turf as Ivey talked to the remaining players. A teammate helped O'Neal off the field as the other players left the workout, the newspaper reported.
A dozen players participated in the session. In line with NCAA rules, no members of Missouri's football coaching staff attended the non-contact workout. Players were dressed in T-shirts and cleats but no helmets or pads.
O'Neal, a four-sport standout in high school, was listed third on the Tigers' depth chart at middle linebacker.
Bob Bunton, O'Neal's coach at Parkway North High School, said O'Neal showed no signs of a serious medical problem in high school.
"Aaron had always been a picture of health,'' he said. "It was something he really took pride in."
