(Reuters) - Britain's Simon Yates saw his overall lead over defending champion Tom Dumoulin cut in half up the sharp closing climb to Prato Nevoso on stage 18 of the Giro d'Italia on Thursday.
German Maximilian Schachmann won the 196km stage from Abbiategrasso after capitalizing on a breakaway to finish ahead of Spaniard Ruben Plaza Molina and Italy's Mattia Cattaneo.
But the biggest drama was played out well behind the leaders in the main pack, with Yates, who started the day with a 56-second lead over Dutchman Dumoulin, dropped in the final few kilometers to blow the race wide open.
World time-trial champion Dumoulin followed an attack by four-times Tour de France champion Chris Froome to finish just ahead of the Team Sky rider, as Yates struggled badly for the first time at this year's Giro.
"I didn't have great legs but did the best I could. I'm still in front so it's all good," an exhausted Yates said after the race.
Dumoulin was cautiously optimistic and clearly pleased to have picked his moment so well to get within 28 seconds of Yates in the general classification.
"I was waiting until the moment and with two kilometers to go I tried to see what was possible," he said. "Yates responded to my first attack and then Froome attacked and I tried to follow and I suddenly found (Yates) was dropped so it was nice."
Italian Domenico Pozzovivo is third in the general standings, with Froome in fourth place, three minutes 22 seconds behind Yates.