Belgian's Tim Wellens enjoyed a red letter day on the Giro d'Italia Thursday with his maiden Grand Tour stage win as Tom Dumoulin held onto the leader's pink jersey. The 25-year-old Wellens broke early and powered up the final 18-kilometer climb to Roccaraso to come home alone after the 157km sixth stage. On the 2016 Giro's first gentle taste of mountain air Dumoulin held off challengers for his pink jersey, finishing fourth. Looking in good shape the Dutch rider took a fistful of seconds off some of the main contenders for outright victory like Italy's Vincenzo Nibali, and Spanish duo Mikel Landa and Alejandro Valverde. Astana's Jakob Fuglsang got closest to Wellens, the Danish rider reaching the race's first summit finish in second, 1min19sec behind, with Russian Ilnur Zakarin on his rear wheel in third. In the overall standings Dumoulin now leads Fuglsang by 26sec, with Valverde 41s away and Nibali 47. Wellens made his stage-winning move 15km out, when he slipped free from his companions in the breakaway, first Eugert Zhupa and Alessandro Bisolti and then Laurent Didier and Pim Ligthart. "It was ideal with Pim Ligthart attacking from the front," Wellens said. "We bridged to the front leaders, and the front leaders were already tired. On the last climb I was the strongest. I had a very good feeling." One of the rising stars of Belgian cycling Wellens was giving himself the perfect present to mark his birthday Tuesday. Up to this point he had come in second twice in stages on his first Giro in 2014, won last year's Grand Prix de Montreal, and claimed the closing stage in this year's Paris-Nice. He celebrated his career high by picking up his bike and waving it over his head. Friday's seventh stage is a 211-km ride from Sulmona to Foligno favoring the sprinters despite a second category climb. — Agencies