Tadej Pogačar won his third stage of the Vuelta a España in Castellón on Thursday – but only after the world champion was surprisingly caught on the finishing climb and went off the road on its tight descent.The sixth stage of the race exploded into action in the final 30km, when the peloton tackled the category one ascent of Puerto El Bartolo that included 1.9km of rough gravel terrain.Pogačar was paced up the lower slopes by his 20-year-old UAE Team Emirates-XRG teammate Pablo Torres, before attacking 3.7km from the top. Primož Roglič, second overall, Oscar Onley, Richard Carapaz and Felix Gall kept with him for 300m before he went clear just before the section of sterrato began.More than accustomed to riding on gravel — he’s won Strade Biache four times — Pogačar’s time gap was said to be around 50 seconds to the remaining members of the GC cohort. But towards the end of the off-road sector, Movistar’s Enric Mas surprisingly closed in on him and passed him over the top of the climb. Only Jonas Vingegaard, Mathieu van der Poel and Jhonathan Narváez have beaten Pogačar up a climb in the last three years.Midway down the narrow, steep descent of the Bartolo climb, and just moments after Mas had told him to slow down, Pogačar rode off the tarmac and was forced to unclip from his pedals. He did well to escape falling off his bike.The pair then stayed together until the finish line where Pogačar predictably beat Mas in a two-up sprint. The Spaniard, however, did overtake Roglič in the general classification and now sits second, 3:34 adrift of Pogačar.The least expected day: Enric Mas surprises PogacarThat Pogačar took more time out on most of his rivals was not a surprise. What was not expected was that Mas of all people, a much-maligned rider despite four Vuelta podiums on his palmares, would catch him on the day’s final climb. Pogačar simply doesn’t get caught in Grand Tour racing anymore.