MELBOURNE - Sebastian Vettel was heartbroken that "reliability issues" with his Red Bull Renault again cost him a potential Grand Prix victory in Australia yesterday.

The 22-year-old German, who had the fastest car in qualifying and led the field up until lap 26, encountered brake problems that forced him out of contention.

It was a repeat of Vettel's drive in Bahrain a fortnight ago, when he also started from pole and led for 34 laps before mechanical problems spoilt his race.

It capped a dismal day for the flying Red Bulls, who had both cars start off the front row of the grid but only finished with Mark Webber's struggling ninth after he collided with McLaren's Lewis Hamilton on the penultimate lap.

"There was nothing I could have done, I lost the car and that was it," said Webber.

The collision cost Hamilton a place on the podium.

"I apologise to Lewis about that. I lost all down-force in the front of the car when I got close to them, the car lifted and I slidinto the back of him," Webber said.