By Ian Ransom
MELBOURNE (Reuters) - Lewis Hamilton's world championship defence got off to a flying start on Sunday with a crushing victory for Mercedes in the season-opening Australian Grand Prix as Formula One rivals succumbed to a farcical rash of reliability problems.
Pole-sitter Hamilton started from a grid reduced to 15 cars from a possible 20 and cruised to his 34th race win with a 1.3-second gap to runner-up team mate Nico Rosberg.
With Mercedes enjoying a Sunday stroll, Sebastian Vettel finished third -- 34 seconds behind Hamilton -- on his Ferrari debut after winning a battle for the podium with Williams driver Felipe Massa.
Ferrari's cheer was tempered, however, by two botched tyre changes for Kimi Raikkonen, the second forcing the Finn to retire when fifth late in the race due to his left rear wheel not being properly attached.
Interviewed on the podium by Arnold Schwarzenegger, the Hollywood 'Terminator', Hamilton said it was great to be back on top.
"It is an incredible feeling to continue winning," he said.
Max Verstappen's record-setting turn as the youngest ever F1 driver ended on a sour note when the Dutch 17-year-old rolled to a stop near the pit entry after complaining of smoke in the cockpit of his Toro Rosso.
Only 11 cars finished, with both Lotus drivers out before the end of the first lap on an embarrassing day for a series that prides itself on being the pinnacle of motorsport.
McLaren's Kevin Magnussen, standing in for the absent Fernando Alonso, and Red Bull's Daniil Kvyat were unable to start after both suffered failures on their formation laps.
The two Manor Marussia cars were scratched on Saturday after failing to participate in qualifying or any practice sessions, while Williams driver Valtteri Bottas was ruled out of the race with a back injury less than an hour before the start.
After a chaotic start that saw Lotus driver Pastor Maldonado crash into the barrier on turn two after being nudged from behind, Hamilton and Rosberg sped away from the chasing pack.
Opening a 15-second gap to third placed Felipe Massa after the 20th lap, Hamilton successfully kept his team mate Rosberg at arm's length.
Following a week of legal battles, Sauber were buoyed by a fifth place finish for Brazilian rookie Felipe Nasr, gaining their first points since 2013.
It was the best finish by a Sauber rookie, with Nasr's team mate Marcus Ericsson and Red Bull's Carlos Sainz also earning their first points by finishing eighth and ninth respectively.
Local hero Daniel Ricciardo had a terrible start and his Red Bull lacked pace but he battled hard to finish sixth in front of home fans.
It was a dark day for Honda-powered McLaren, however, with Jenson Button finishing last of the 11 cars and lapped twice by Hamilton and the leaders.
Force India driver Sergio Perez had an eventful afternoon, being instructed to drop back two places after over-taking illegally when the safety car was out early.
He then overcame a collision with Button in a battle to avoid the indignity of last place.