Beijing  - Defending champion Felix Sanchez, of the Dominican Republic, on Friday resigned his gold medal against a dramatic backdrop: his grandmother died on the same day.

"I got a call today (Friday) at 8 in the morning, and they told me my grandmother had died. It totally threw me off my feet. It was a very difficult day for me. My heart was anywhere but on the track," Sanchez said.

He ran the distance in 51.10 seconds, a time unfit for an Olympic champion.

In Athens, he won the race with 47.63 seconds, and last year he won silver at the World Championships in Osaka with 48.01 seconds.

"I was on the track, before running, and I really wanted to run, but to run out of the stadium," Sanchez told Deutsche Presse-Agentur dpa.

"I have cried all day. I was not in a mood for competing. I grew up with my grandmother, Lilian. She was 72," the athlete said.

Immediately after the race, he went about finding out how quickly he could get back to his home in the US state of California.

Still, Sanchez was glad he competed, despite his poor performance, he said.

"I did well to compete. At least I lost my title in there," he said.

Sanchez - set to turn 31 at the end of the month - ended 22nd out of 25 participants, but he said he will be back in London in 2012. (dpa)