"I'm thinking it's going to be a hit-and-run attack while I am standing in line for food or something," said the American tennis champion, aware there is a price on his head.

"I find it pretty funny, but I'm gonna be like the basketball men, you know. I'm holding out for more money!"

After being knocked out of the doubles tournament on Monday with teammate Mardy Fish, he said: "I've got an inside source who is supposed to be doing the research for me to figure out if they are planning an ambush or what."

Worried by the wind on court, Roddick admitted it was fun to live in the Olympic village.

"It's like being in a college dorm with all the world's greatest athletes and I'm having a ball.

"But we gotta be careful about these girls...!"