08/28/2011 09:36 EDT | Updated 10/28/2011 05:12 EDT

Defending F1 champ Sebastian Vettel wins Belgian GP to extend his overall lead

SPA, Belgium - Defending Formula One champion Sebastian Vettel banished any talk that his grip on the title was slipping by winning the Belgian Grand Prix on Sunday in tough conditions to extend his overall lead with just seven races remaining.

Vettel started from pole position to win his seventh race of the season and 17th of his career. The German led Red Bull to a 1-2 finish with Mark Webber finishing close behind.

"I enjoyed every lap today. The car was fantastic to drive," Vettel said. "If the car does what you want it to do, this place is really fun. It was a very entertaining race, with the strategy to come in early."

McLaren driver Jenson Button overtook two-time former champion Fernando Alonso's Ferrari late in the race to claim third place, but the Briton could not follow up on his Hungarian GP success.

If any of Vettel's rivals had sensed a weakness after the German's failure to win any of the last three races, they only need to look at the leaderboard for a reminder of how far-fetched that now seems.

Vettel has a 92-point advantage over second-placed Webber, is 102 points clear of Alonso, and leads fourth-place Button by 110 points.

"With every race it is getting more and more difficult to close the gap on the Red Bull," Alonso said.

Still, having won his maiden F1 title on the final day last season, Vettel is not getting carried away.

"Things can change quickly, two races you are out and others have good races," he said.

However, Lewis Hamilton's slim title hopes look all but over after he crashed his McLaren early on. He is fifth in the standings, 113 points behind Vettel.

Button, meanwhile, was left to rue what might have been had he not started the race way down in 13th spot on the grid.

"To come away with the third was disappointing," Button said. "Who knows what would have happened if we had qualified well."

The 2009 champion remains confident he can win at the Italian GP in two weeks' time.

"We have to look forward to Monza," Button said. "For me this is the best we've had the car all year."

Vettel secured pole position for the ninth time in 12 races this season. But he had not won in Britain, Germany and Hungary, and only one of the last five heading into Spa, prompting speculation that he was losing his touch.

"Talk is cheap and results are better," his teammate Webber said. "We have brilliant rivals, that's why we have to respond all the time."

Vettel's jubilation was evident at ending his winless run as he stood on top of his Red Bull after the race, and pumped his fists in delight.

"What a race!" he told his Red Bull team over the race radio at the end as he won in Spa for the first time, banishing memories of last year's 15th-place finish.

Tire management proved a crucial factor in Vettel's win on the seven-kilometre Spa circuit — the longest and arguably the most difficult on the F1 calendar.

The 24-year-old overcame significant tire wear early on and held off Alonso when the Spaniard was pressuring strongly.

"We had a lot of concerns going into the race after qualifying and weren't quite sure about the tires," Vettel said.

Twenty years after making his F1 debut on the same track, seven-time former champion Michael Schumacher started from last place after crashing during the first lap of Saturday's qualifying session.

The 42-year-old German drove his Mercedes with panache to finish in fifth place behind Alonso.

Hamilton pushed to overtake Sauber driver Kamui Kobayashi on lap 13 and the two cars collided coming into the corner, prompting the safety car to come out.

"I'm not really quite sure what happened, I hit the wall pretty hard," Hamilton said. "As far as I was concerned I was ahead of whoever I was racing and then I was hit by them."

Vettel seemed to get away quite slowly at the start and Nico Rosberg raced up from fifth place on the grid to overtake him at the Le Combe turn, with Ferrari's Felipe Massa and Alonso both passing Hamilton.

"I thought the engine nearly died for a moment, for a moment it was quite critical," Vettel said. "Then there was a bit of trouble into turn one."

On the next lap, Alonso made a brilliant move to overtake Massa on a corner, while Hamilton also sneaked past the Brazilian to get back into fourth.

Vettel took an early pit stop on the fifth lap to replace his blistered tires with soft tires.

He came out of the pits in eighth place, but soon cut through the field and regained the lead when Hamilton went in for new tires on lap 11. Within minutes, Hamilton was out of the race, despite his team telling him over the radio to "take it easy."

By the halfway stage, Vettel regained the lead but the German had already come in twice to get new soft tires, while Alonso — about five seconds back after 27 laps — was still on one change.

Alonso finally came in to the pits on lap 30, switching to medium tires, followed shortly after by Vettel and Webber, leaving Button to briefly take the lead until he came in for new soft tires.

Bruno Senna, driving in his first GP with Renault after replacing Nick Heidfeld, started from seventh place.

But as several cars bumped and jostled near the back of the grid at the start, the Brazilian slammed into the side of Jaime Alguersuari, who had to pit his Toro Rosso because of a broken track rod.

Senna also pitted and got a drive-through penalty for causing an avoidable accident. He ended up 13th.

Alguersuari and his Torro Rosso teammate Sebastien Buemi retired, as did Australian driver Daniel Ricciardo's HRT, and Mexican rookie Sergio Perez.