Motor racing-Rosberg's lead really is a big deal, says Hamilton

Formula One - Chinese F1 Grand Prix - Shanghai, China - 17/4/16 - Mercedes Formula One driver Lewis Hamilton of Britain before the Chinese Grand Prix. REUTERS/Aly Song

SOCHI, Russia (Reuters) - Triple Formula One world champion Lewis Hamilton has yet to be beaten over the course of a season by Mercedes team mate Nico Rosberg but the Briton is not about to under-estimate the challenge facing him this year.

With Rosberg 36 points ahead of Hamilton after winning the first three races of the year for a maximum 75 points, the Briton rejected on Thursday a suggestion that the difference was no big deal.