SILVERSTONE (AFP) - Australia's Casey Stoner replaced Jorge Lorenzo at the top of the MotoGP standings after winning his fourth race of the season at a soggy British Grand Prix on Sunday. Lorenzo succumbed to the horrendous conditions at a wet and windswept Silverstone, sliding off on lap 10 to allow Stoner to move 18 points clear of the defending champion in the riders' standings after his 150th MotoGP race. Stoner cruised home with a huge 15-second lead, while Andrea Dovisioso, riding in place of the injured Dani Pedrosa, completed a sweet afternoon for Honda by finishing second. American Colin Edwards took third on a Yamaha. Lorenzo stole in front of pole-sitter Stoner on the first bend, but Dovisioso led Stoner past the Spaniard shortly afterwards before the Australian deftly slipped past Dovisioso at the start of lap two. Italy's Marco Simoncelli almost took Lorenzo out of the race on lap four, running wide after a serious wobble and then cutting perilously close to the Yamaha man when he returned to the track. Stoner had shown supreme form throughout the weekend and the 2007 world champion managed to keep his rivals at arm's length despite the slippery conditions and several large puddles of standing water on the track. Two seconds separated the top four of Stoner, Dovisioso, Lorenzo and Simoncelli with 15 laps to go, but Lorenzo's race came to an abrupt conclusion three laps later as he was flipped over the front of his bike after high-siding at Abbey corner. His Yamaha team-mate Ben Spies having crashed out moments earlier, Lorenzo stalked away from his prone machine in frustration and his mood was not improved by the sight of Stoner promptly setting the race's fastest lap.