Eritrean rider Biniam Girmay has become the first man from his nation to win one of cycling's cobbled classics by taking out the prestigious Gent-Wevelgem race on Sunday.

The 21-year-old out-sprinted a group of four riders in the final 250 metres to claim the biggest victory of his career.

"I never imagined ending this day with a victory," Girmay said via his Intermarché-Wanty-Gobert team after the race. 

"It is so difficult to race the Flemish classics without experience.

"I want to thank my team for their belief in me."

Girmay showed poise and tactical nous beyond his years to be in contention during the arduous 249km trek through the cobbled streets and sharp climbs of Flanders' fields.

The Eritrean attacked with Christophe Laporte, Dries van Gestel and Jasper Stuyven with 27km to go on the flat run in to the finish after summitting the final cobbled climb.

The select group of four worked together to keep the chasing peloton at bay and set up a dramatic finale.

"It was only in the final kilometres that I started to believe in the victory," Girmay said.

Laporte finished second with van Gestel third.

The victory in such a big race, the first for a rider from sub-Saharan Africa, is being noted as a huge moment for African cycling.

Girmay, who won a silver medal in the under 23 race at last year's world championships, is flying the flag for black African riders in the peloton.

He told Eurosport earlier this year that often he would be the only black rider in the professional peloton and that his world championships silver medal was a big moment not only for him, but "for my continent, for Eritrea and especially for black cycling, to show our potential to the world".  

Former Giro d'Italia winner Tao Geoghegan Hart wrote on Twitter that he was "shaking" watching the finale.

"This is unbelievable and unreal... I'm shaking from watching that, it's been so incredible," he wrote.

"Eritrea, I think you and your readers are aware how massive cycling is for the nation. This will just be incredible for them."

Girmay was only racing in this Belgian Classic due to a last-minute change of plan after his fifth-place finish in Friday's E3 Saxo Bank Classic.

With such an assured performance, there have been calls for him to remain in Belgium for next week's Tour of Flanders.

However, Girmay told reporters that he will return back to Eritrea as planned to see his wife and son before completing high altitude training ahead of the Giro d'Italia in May.