Great Britain will not be represented in the shot put final after Carl Myerscough failed to qualify from his third attempt.
The Brit finished in 14th place in Group B of the qualifying round and 29th overall in the standings after posting an 18.95m as his furthest throw.
"I probably just tried a little too hard and it didn't come off," Myerscough told the BBC. "It's a massive disappointment. I felt great out there.
"I've probably never felt better. The adrenaline was enormous. I just didn't relax enough and it just didn't click."
Reese Hoffa of the United States, who is the favourite for a gold medal, qualified at the top of the pile with a throw of 21.36m.
The final is due to take place at 8.30pm this evening.