Greene ran a season's best 9.94 seconds in June
Olympic champion Maurice Greene insists he is ready to confound the sceptics and win a fourth world 100m title in Paris.
The American has struggled for form for much of the last year but ran 9.94 seconds in June - the second fastest time of the season.
"A lot of people don't think I will be able to win again, but I think I am about to shock the world," said Greene.
"I think 9.94 could win Monday's final but I'm going to run 9.80-something."
Greene denied his chances would be hampered by injury problems.
"I don't have tendinitis," he said. "I have had some problems in the past, but who cares about those problems?
"The bottom line is, you've got to be ready to run. You can't make excuses."
Greene claims he is not concerned about reclaiming the world record from compatriot Tim Montgomery.
"I am not thinking about a world record right now," said Greene. "All I am thinking about is winning.
"Nothing else matters to me this season but winning the world championship."
Greene is desperate to outdo Carl Lewis, who is the only other man ever to win three consecutive 100m world titles.
"To be the first to win four would mean a lot to me because I love doing things people have never done before," said Greene.