Germany's Nico Rosberg won the showcase Monaco Grand Prix for the second year in a row on Sunday to snatch back the Formula One world championship lead from Mercedes team-mate Lewis Hamilton.

Rosberg's second victory of the season, from a controversial pole position that increased the tension between the two title rivals, took his points tally after six races to 122 with Hamilton on 118.

The Briton, who complained 13 laps from the end that he had something in his eye and could not see properly, was second as a dominant Mercedes chalked up a sixth win in a row and fifth successive one-two finish.

"It's another special day for me, for sure," said Rosberg of his fifth career win.

"Lewis drove well and pushed me massively hard. The pressure was on but I kept it cool and pulled a bit of a gap at the end."

Australian Daniel Ricciardo took third after chasing Hamilton nose-to-tail to the finish while quadruple world champion team-mate Sebastian Vettel, in his 100th race for Red Bull, retired after eight laps with a power unit problem.

After coping with two safety car interludes, Rosberg took the chequered flag 9.2 seconds ahead of Hamilton after the two had spent the first half of the race with little to separate them.

Hamilton, who had been embroiled in controversy on Saturday when he suggested Rosberg might have deliberately brought out yellow flags in qualifying to prevent the Briton beating him to pole, had a comparatively low-key afternoon.

The wheel-banging drama and Ayrton Senna-Alain Prost style rivalry that some had expected, or hoped for, never materialised and Hamilton's hopes faded when he told his team about his vision problem.