Spain's Luis Leon Sanchez won the 144km opening stage of the Tour of the Basque Country Monday ahead of compatriot Dani Navarro. The 32-year-old Astana rider Sanchez and Navarro of Cofidis escaped on the descent of the day's final climb, the Aiastia, 10km from the end of the stage from Exebarria to Markina-Xamein. Australian Simon Gerrans of the Orica-GreenEdge team won the bunch sprint to finish third in the same time as the winner. "I was desperate to accelerate to overtake Dani Navarro (in the sprint finish). There wasn't much space but I had to take it, and that's what happened," said Leon Sanchez. Giro d'Italia champion Alberto Contador, Vuelta a Espana winner Fabio Aru and Tour de France runner-up Nairo Quintana are amongst the favorites for overall victory in the week-long stage race which ends Saturday. Contador attacked several times on the undulating course but came home in the main bunch alongside Quintana, who was suffering from the residue of a virus. "The stage was very tough due to the rain that fell all day long," said Contador. Tuesday's second stage has four categorized climbs on the 174.3km route from Markina-Xamein to Amurrio. Paris-Roubaix worries Paris-Roubaix organizers admitted Monday they were worried they may have to change Sunday's race course due to mud on the cobbles. The 'Hell of the North' is the third of the year's 'Monument' one-day classics and one of the most prestigious races on cycling's calendar. World champion Peter Sagan will enter the 'Queen of the Classics' as hot favorite after winning last Sunday's Tour of Flanders — the second Monument. But the 114th edition of Paris-Roubaix may not follow the exact advertised route as some of the 27 cobbled sectors are currently considered too dangerous to ride. "The route is wet and muddy. We had some surprises, especially on the first (cobbled) sector in Troisvilles due to a large covering of mud," said race director Thierry Gouvenou after Monday's reconnaissance of the route with journalists. "We'll wait a few days before taking a definitive decision. If we had to race today (Monday) we'd have to avoid that section. But there is still time and experience shows that you have to be patient." This year's Paris-Roubaix race will be 257.5km long and starts in Compiegne, just outside Paris, before finishing at the old velodrome in Roubaix. The 27 cobbled sectors encompass 52.8km of the dreaded 'paves'. As well as Sagan, three-time former winners Fabian Cancellara and Tom Boonen will be expected to shine, but last year's champion John Degenkolb misses out due to injury as he continues to recover from a crash with a car in February. — Agencies