DIJON, FRANCE, JULY 25 -- Stephen Roche of Ireland virtually assured himself of victory in the men's Tour de France today by taking a 40-second lead over Spain's Pedro Delgado with just one day to go.

Roche defeated Delgado by 1 minute 1 second in the 24th-stage time trial to take the overall lead.

Jean-Francois Bernard of France had the best time in the stage, 48 minutes 17 seconds, on the 23.6-mile course around Dijon. But Roche's second-place time, 1:44 behind, was enough to assume the overall lead.

Delgado came in seventh, 2:45 behind Bernard, and that erased the 21-second lead he had over Roche at the start of the day.

The final stage Sunday will be a flat 119-mile course from Creteil to Paris.

Though the winner of the Tour de France has emerged in the final stage before, as in 1968 when Han Janssen of the Netherlands came out of nowhere to take the championship, such an event is rare and Roche seems nearly assured of victory on the Champs Elysee Sunday.

If he holds on, Roche will become the first Irishman to win the Tour de France and only the second English-speaking rider; American Greg LeMond, who won the race last year, was the first. LeMond, who was injured in a hunting accident, did not compete this year.

"I'm happy to be ahead, by one second or 40," said the 27-year-old Roche. "I just wanted to close the gap and make sure I would wear the yellow jersey tomorrow in Paris."

Roche also would go down in cycling history as the fifth rider to win both the Tour de France and the Tour of Italy in the same year. The others were Italian Fausto Coppi, Belgian Eddy Merckx and Frenchmen Bernard Hinault and Jacques Anquetil

Merckx, Hinault and Anquetil each have won the Tour de France five times.

Delgado, the PDM team leader, took the overall lead with strong performances in five stages in the Alps this week, but Roche was outstanding Thursday and Friday to cut the Spaniard's lead.

Roche had been expected to defeat Delgado, a mountain specialist, in the mainly flat time trial. He gained five seconds on Delgado in the first mile and steadily increased his lead with a smooth ride, mainly against the wind in a light rain.

"I'm disappointed, but I knew that Roche was much stronger than me in the time trials," Delgado said.