Nico Rosberg can beat Lewis Hamilton - Mercedes team principal

Mercedes team principal Toto Wolff has backed Nico Rosberg to keep Lewis Hamilton honest throughout the 2015 Formula One season.

Hamilton has finished ahead of Rosberg in all four races so far this year, with the reigning F1 champion winning three.

It continues the Brit's dominance of his Mercedes team-mate from 2014 where Hamilton won 11 races to Rosberg's five.

But Wolff is convinced Rosberg is closer to Hamilton than many give the German driver credit for, and insisted the 29-year-old will ensure this year's drivers' championship remains tight.

"When you look at their performance in qualifying in China, for example, there were just four hundredths between them," Wolff told Autosport.

"That is not someone who is clearly beaten.

"That is a tiny little edge, which was enough for Lewis to make it on pole and control the race.

"It could have been completely different if Nico had been on pole.

"Nico wouldn't be in Formula One as a multiple race winner and a challenger for the championship if he allowed himself to be destabilised after a few races.

"I fully expect him to come bouncing back. I don't know when it will happen, but he's always going to be there, no doubt."

Hamilton (93 points) already has a 27-point gap on second-placed Rosberg in the 2015 drivers' championship standings with Ferrari's Sebastian Vettel (65) and Kimi Raikkonen (42) the Mercedes pair's closest rivals.