Vettel sure Red Bull can improve on P5

Sebastian Vettel believes Red Bull can be the second quickest team at Suzuka but says Mercedes' pace looks ominous ahead of the Japanese Grand Prix.

Lewis Hamilton and Nico Rosberg were over a second clear of the rest of the field in FP2, with Valtteri Bottas and Jenson Button in third and fourth ahead of Vettel. While Vettel is sure Red Bull can improve, he thinks third is as high as it can realistically aim.

"I think we can definitely do better than fifth, but we've probably hit the limiter in third position!" Vettel said. "Mercedes seems to be very, very quick around here but I think we can improve, especially on the short run."

And Vettel also believes McLaren has made a step to ensure there are a group of four teams fighting for best of the rest.

"It would be nice to fight [Mercedes], who knows if it rains? But other than that I think it's the usual suspects so Williams, McLaren seems to be a bit stronger here and Ferrari."

Focusing on where his car can improve, Vettel said Red Bull needs to work on finding a better balance ahead of qualifying.

"Obviously the last couple of years we were in a bit better shape after the Friday, so we're not yet where we want to be. The balance of the car we can improve, so we need to work on that - especially on a short run - and then see what the weather does tomorrow and Sunday."