Nico Rosberg has admitted that it is imperative he prevents teammate Lewis Hamilton from winning his fourth successive race this weekend.

The Mercedes duo have shared the success in the opening four races of the season, but Rosberg believes that it is crucial Hamilton is not the driver celebrating once again when the Spanish Grand Prix finishes on Sunday.

"Every weekend is crucial, but the results momentum is on his side and I need to try to turn it around," the German told reporters.

"Definitely that is the case. I have come here to win, to try to extend the lead in the championship.

"What I need is a normal weekend and then I'm sure I'll be able to turn things around."

Rosberg currently leads Hamilton by four points in the drivers' standings.