Sebastian Vettel admitted he was surprised by Mercedes' ability to improve across the final Q3 runs during qualifying for the Bahrain Grand Prix.
Vettel provisionally held second on the grid after the first runs but Nico Rosberg improved while Lewis Hamilton vaulted from fourth to first, setting a new lap record en-route to pole position.
Vettel remained over half a second behind Hamilton and will start the race from third on the grid.
"There's nothing really to complain about," he said. "It's a big surprise that both Lewis and Nico in the end were able to improve so much.
"For me the track was similar to the run before and that's why the time was practically the same.
"We know we are not yet where we want to be but I think we are pushing very hard though.
"Obviously the season has started already so it's up to us to make sure we keep making technical progress, but as I said many times the car is a big improvement to last year and this will provide more opportunities to improve also in the future; but we really have to keep up the pressure.
"You can talk about what can happen in ten races but we have to focus first of all on tomorrow, prepare the race as good as we can because there's a chance to do well and to win."