BARCELONA: Formula One leader Sebastian Vettel held off closest championship contender Lewis Hamilton for his fourth victory of the season at the Spanish Grand Prix Sunday. The Red Bull driver took the lead for good after the second round of pit stops to edge Hamilton by 0.6 seconds and widen his advantage atop the standings to 41 points over his McLaren rival. Vettel's fourth win in five races this season was the first in 11 GPs at the Catalunya Circuit from a driver not starting on pole. Vettel lost use of his KERS speed boost and Hamilton snuggled in right behind him, but the German driver clung to his slim lead over the last dozen laps to become only the fifth winner in 21 races not to start at pole in Barcelona. Red Bull teammate Mark Webber surrendered pole position to finish fourth behind Jenson Button of McLaren, while Fernando Alonso of Ferrari led for the first 18 laps before settling for fifth in the hot conditions. Vettel's first Spanish win increased his overall total to 118 points after five races with Hamilton remaining the closest challenger with 77 points, and Webber third on 67 points. Alonso remained fifth in the standings with 51 points – 10 behind fourth-place Button – despite a gutsy start in front of his home crowd. Alonso steamed up the inside past the top three to lead into the first corner, with Webber's concern over the Spaniard allowing Vettel to go around his teammate from the outside to stay second. Alonso held his lead for 18 laps until the second round of stops when the Ferrari driver re-emerged behind Vettel and Hamilton and ahead of Webber, who engaged Alonso in a number of overtaking swaps but couldn't get ahead until after the final round of stops. Button stayed out as the leaders went in for a third tire change and the McLaren driver's better grip allowed him to get past Webber and Alonso into third by the halfway point. Button, the 2009 winner here, built enough of an advantage and was the only car among the top-5 not to go on a three-stop strategy. Hamilton started making gains when Vettel lost his KERS but he couldn't get past despite the extra overtaking boost and the adjustable rear wing also offering an extra push. Button and Webber finished within 50 seconds of Vettel, while Alonso and the rest of the field were lapped by the top-two. Michael Schumacher secured sixth for his best finish of the season in front of Mercedes teammate Nico Rosberg, while Nick Heidfeld finished eighth after starting last in the Renault garage. Sauber pair Sergio Perez and Kamui Kobayashi rounded out the top