PARIS (AP) - Formula One world champion Sebastian Vettel heads to the Belgian Grand Prix trying to figure out how to make up a 42-point deficit on overall leader Fernando Alonso _ and how to prevent others from overtaking him as Alonso's main rival.
Last season, it was the opposite as rivals sought to catch Vettel's unstoppable Red Bull. This weekend, the German faces competition in a thrillingly wide-open championship.
The two-time F1 champion sits in third place overall heading into Spa, two points behind teammate Mark Webber. Former champions Lewis Hamilton and Kimi Raikkonen are within five and six points of Vettel, respectively.
"It's going to be an extremely tough, tactical and interesting finale to the season," said Hamilton, the 2008 F1 champion.
Vettel won five of the six opening races last season before a minor slump offered his rivals a glimmer of hope. Vettel had been beaten in four of his last five races heading into last year's race in Spa, yet was still more than 80 points ahead of his challengers and went on to win the race from the pole.
He needs to do so again on Sunday, because there are five drivers in realistic contention for the F1 title, with only 48 points separating Alonso in first and Finn Kimi Raikkonen in fifth.
"There's no team with a clear advantage, although we're all pushing hard to catch Fernando's points tally," Hamilton said. "There's still everything to play for."
The 25-year-old Vettel badly needs to win in Spa in order to stop Alonso edging closer to his third F1 title. Webber _ at the age of 36 _ is meanwhile proving a tough adversary within the Red Bull camp with wins at Monaco and the British GP this season. Vettel's only race win came at the Bahrain GP in April and he has managed only three podium spots in 11 races so far.
Still, he thinks Spa suits him.
"The Spa circuit is defined by the surrounding nature and it's one of my favorite tracks. I was very happy to have won there last year," he said. "Spa offers every type of racing corner _ ultra-fast, medium-fast and slow chicanes that alternate with fast straights. The difference in altitude and the unpredictable weather really make the track a big challenge."
The 7.004-kilometer (4.352-mile) circuit is the longest track on the calendar and _ along with Monaco _ the most demanding. Corners such as Eau Rouge and Blanchimont push drivers and tires to the absolute limit.
"Spa is the best track to have after a break and it's extremely rewarding for drivers at that venue. It's obviously remained pretty much unchanged for some time and it has a lot of character," Webber said. "It's one of the classic tracks where you feel like an F1 car belongs on the circuit. We're looking forward to going there and challenging for the victory."
Because of the vast size of the track, different microclimates lead to variable weather conditions _ meaning it can be raining on one part of the track and sunny at another.
Hamilton, who won at Spa in 2010 is brimming with confidence after heading into the month-long summer break with a victory at the Hungarian GP last month.
"My win in Hungary was a fantastic way to go into the summer break. It had the added bonus of sending the whole team away for their holidays with a positive feeling in their hearts," Hamilton said. "It's also given me the hope and assurance that we can come back for the final nine races with a real chance to go for both world championships."
Raikkonen is one point behind Hamilton and, although seeking his first win of the season, the 2007 F1 champion has been driving consistently with five podium spots, including second place behind the British driver in Hungary.
A win for Hamilton or Raikkonen on Sunday would continue to throw the championship open and increase the pressure on Vettel.
"Given the unpredictability of the sport, I think it's still difficult to predict accurately who'll win the next grand prix," Hamilton said. "But I reckon the coming few weeks ought to give us a much clearer idea of the destination of the world title."