Paris ? American Tim Montgomery turned the late-season IAAF Grand Prix Final into his showcase.

Montgomery set a world record in the 100 meters Saturday, clocking 9.78 seconds and dethroning Maurice Greene as the king of sprint.

Helped by a quick start and a strong wind on a sunny day, Montgomery cut .01 off the previous world record of 9.79, set by Greene in 1999.

Greene, the Olympic and world champion, watched Montgomery’s run into the record book from the stands Saturday.

Montgomery stunned the small crowd at the half-empty Stade Charlety, beating Dwain Chambers of Britain, who finished second in 9.87. American Jon Drummond was third in 9.97.

“I knew something special was in me,” Montgomery said. “I can say I’m the fastest man to ever run the 100 meters.”

Greene withdrew from the Grand Prix Final citing fatigue, but stayed in Paris and watched the event.

“An athlete can have a magical day, and today he had a magical day,” Greene said. “Everything clicked for him.