Sebastian Vettel admitted Suzuka has become more challenging with the current generation of F1 tyres.
He said: “The circuit seems pretty tricky this year on these tyres – they make the cars seem more alive, so Sunday will be an interesting race.
“Taking 130R with the DRS open isn’t as easy as it used to be!”
Vettel ended the first practice session in the barrier at Degner after going off. He said: “It wasn’t a big mistake this morning, but in that moment I wasn’t 100% awake and mistakes around here can be quite costly.
“I went off and tried to slow the car down, but I hit the wall slightly. It wasn’t a big impact, but it did some damage to the car, so it wasn’t perfect.
“It did affect our run plan a little, but we had a solid afternoon.”
2011 Japanese Grand Prix
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