SARZEAU, France

Fernando Gaviria and Peter Sagan have turned the first four days of the Tour de France into an enthralling duel of rising star versus world champion.

And Tour newcomer Gaviria is winning so far.

Gaviria edged Sagan at the finish line to claim Stage 4 on Tuesday and take his second stage win in his first participation at cycling’s greatest race.

The 23-year-old Colombian had already bettered Sagan in a sprint to take the opening stage, amid rising expectations since his four stage victories at last year’s Giro d’Italia.

Sagan hit back by winning Stage 2 in an uphill sprint after Gaviria had fallen in a group pileup on the final corner.

Tuesday’s flat leg with its four-kilometer finish — the longest straightaway to conclude a leg on this Tour— was perfect terrain for the budding rivals to break the tie.

After Quick-Step hunted down the breakaway to set up Gaviria, he powered ahead of the pack with handlebars swinging and crossed just inches ahead of Sagan and Andre Greipel in a close third.

Sagan was closing fast and seemed to be on pace to overtake him just when Gaviria hit the line.

Gaviria finished the 121- mile leg from La Baule to Sarzeau that started and finished on the Atlantic coast in 4 hours, 25 minutes, 1 second.

Defending champion Chris Froome of Sky, who remained 55 seconds back due to his fall in Stage 1, finished safely in the pack with leader Greg Van Avermaet.

Riders were enjoying a calm sunny afternoon until a pileup near the front of the peloton with just over 5K left that sent several riders to the tarmac.

But there were no changes among the title hopefuls.

A four-man breakaway opened up a gap of more than seven minutes early on, but they were slowly reeled in by the Quick-Step-led pack with 2 kilometers to go.