Mat Coch writes:

Tyre strategy was the talk of the paddock following the opening day of practice for Sunday's Singapore Grand Prix.

"You've probably got at least 1.5 seconds difference between the tyres," explained McLaren's Sam Michael. Pirelli expects the difference to be more in the region of two seconds, some half a second more than even they anticipated.

Pirelli opted to supply the supersoft and medium compound tyres for the weekend, the first time there has been a single step difference between tyre compounds in 2013. It has left teams with a difficult job as they look not only to the race, but formulating their strategy for qualifying.

It is expected teams will opt to run the red-walled supersoft tyre for most of the race. With an expected range of up to 25 laps on a two-stop strategy it leaves teams with a ten-lap stint on the medium compound tyres at the end of the race.

The problem however will be taking enough fresh supersoft tyres into the race to reach that 25-lap target, especially for those on the fringes of the top ten.

"They will have to play that carefully because of the two second difference in performance (between compounds)," said Pirelli's Paul Hembery.

Adding to the headache is the relatively short life expectancy of the medium compound tyre.

"We did have a question mark on the mediums to see how teams would get it going," Hembery smiled. "We've got from five corners to 22 laps as the current range between the teams.

"The medium has the unfortunate situation where if you're running maybe not enough downforce on the rear you're getting wheel slip," he added. "We did know the supersoft was going to be the race tyre and I think you'll see people really pushing that out and minimising the laps on the medium to maybe 8 to 10 at the end of the race."

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