Baseball player Darryl Kile died from a blocked coronary artery bringing on a heart attack, a post mortem has found.

The St Louis Cardinals pitcher was found dead in the team hotel on Saturday.

Police said there were no signs of entry or foul play and it appeared Kile had died in his sleep of natural causes.

After a preliminary autopsy on Sunday, Dr Edmund Donoghue said Kile had an 80-90% narrowing of two of the three branches of the coronary artery, which carries oxygenated blood away from the heart.

It has been revealed that Kile's father died shortly after a heart attack in his mid-40s in 1993.

Dr Jim Loomis, assistant team physician, said on Saturday that the 6ft 5ins pitcher had no known health problems and was not on medication.

About two hours before Saturday's game against the Cubs was scheduled to begin, Cardinals players realised Kile was not at the ballpark and called the hotel to check on him.

Workers at the downtown Westin Hotel forced their way into Kile's 11th-floor room because of the safety latch on the door.