BUDAPEST, Hungary (AP) - The pressure will be on tire manufacturer Pirelli, similar to those trying to catch Formula One leader Sebastian Vettel at this weekend's Hungarian Grand Prix.
While Vettel's rivals try to stop him from extending his lead before the mid-season break, Pirelli hopes its much-lamented tires withstand the hot temperatures expected Sunday outside Budapest.
Last week, the teams held in-season testing sessions at Silverstone to assess new tires provided by Pirelli,. Several spectacular blowouts on the same circuit at the British Grand Prix in June prompted a strong response and boycott threat from drivers.
``We haven't asked for different tires, we have asked for tires that are safe,'' three-time defending champion Vettel said. ``It's hard to know what to expect here.''
Under intense pressure, and following its own investigation, Pirelli decided that from this race until the end of the season, it will revert to last year's tires. Those tires are combined with the current compounds from this season.
Even before Silverstone, there were repeated problems - with the Spanish GP in May turning into a pit-stop procession as tires shredded like paper. At Silverstone, they exploded on four cars, including those of Lewis Hamilton and Felipe Massa. Drivers threatened to withdraw from the German Grand Prix if more blowouts occurred during the race.
Vettel won that race to open up a 34-point lead over two-time champion Fernando Alonso - who has not won since his 32nd career GP in front of his home fans in Barcelona. In the four races since, he has managed two podiums, fourth and seventh place, as Ferrari searches for consistency.
``The second half of the season will be extremely tough, lots of races in only a few weeks,'' Vettel said. ``With the points system we have, obviously it's a very good position we are in at the moment.''
If all goes to plan, drivers will have to focus only on racing this weekend after efforts by Pirelli and FIA to appease tensions led to in-season testing on July 17-19 at Silverstone.
The testing was open to all drivers except Hamilton and Nico Rosberg because Mercedes was excluded as a punishment for holding unsanctioned tire tests after the Spanish GP. Pirelli will provide medium and soft tires for the Hungaroring.
``It would definitely help if we were there,'' Hamilton said. ``(To) have an understanding of how to set the car up with the new tires and see what characteristics they have and how they behave on long runs.''
Mercedes has excelled in qualifying - starting five of the last six races from pole position - but lacks speed over an entire race. Rosberg has two GP wins, both from the front of the grid, while Hamilton has none.
``We've got a lot of work to do to continue our race pace,'' Hamilton said. ``It's going to be tough this weekend.''
Lotus, one of the teams that had the least amount of trouble with tire degradation, did not test the Pirellis at Silverstone, choosing instead to let their young drivers test race.
``It was better for the team,'' Raikkonen said.
Vettel does not read too much into the Silverstone testing, either.
``The test last week was very limited with what we could do with the car,'' Vettel said. ``We probably didn't learn that much. We couldn't really change anything on the car.''
On Thursday, Pirelli announced the compounds for the first three races after the four-week break. Medium and hard tires will be used at both Spa and Monza for the Belgian and Italian GPs, with supersoft and mediums for the nighttime Singapore GP, where the supersofts are ideal on the tight and twisty track.
With 14 corners and short straights, the Hungaroring is the second most difficult track to overtake on after Monaco.
A hot, sunny day is forecast for the race Sunday with temperatures expected to reach 104 degrees.
Since winning in Hungary in 2005, Raikkonen has been second at the Hungaroring three times and third once.
The Finn still has an outside shot of winning his second F1 title, 41 points behind Vettel in third place. But Hamilton, whose win in Hungary last year was his third on the Hungaroring, has not finished higher than third so far this season and trails Vettel by 58 points.