Highlights - Australian Grand Prix
Red Bull's Sebastian Vettel says he is concerned by his car's reliability after technical problems denied him victory in the Australian Grand Prix.
The German was forced off by a wheel problem while leading, two weeks after he slid from first to fourth in Bahrain with a faulty spark plug.
"It'd be better to have 50 points instead of 12 but that's life, we can't change it, it's happened," he said.
"If it continues we won't have good cards in hand for later in the season."
As at the season-opening race in Bahrain, Vettel qualified in pole position, and he did well in wet conditions to open up a substantial lead.
But on lap 26, he ended up in the gravel and another good chance of victory was snatched from his grasp.
"A lap or a bit earlier I felt something was wrong," he said afterwards.
"I had sparks from the front-left wheel, we didn't know what it was.
"I wanted to pit in that lap, I had huge vibrations but approaching turn 13 I was cautious - as soon as I touched the brake, it felt like the disc exploded."
Team chief Christian Horner could only look on in despair as first Vettel's chance of victory vanished, and then his team-mate Mark Webber was involved in a shunt with Lewis Hamilton.
The Australian, who had started second on the grid, ended up coming home ninth and was formally reprimanded after the race over the Hamilton incident.
Vettel worried about Red Bull reliability
"It's the second race in a row we've had a commanding lead and it's desperately frustrating not to convert it," said Horner.
"It's an issue we need to understand. The next race is a week away - there's a long way to got but we need to start winning races."
Webber also failed to make the most of the fastest car on the grid.
He was in sixth place in the closing stages on the back of a five-car battle for second place when he ran into the back of Lewis Hamilton's McLaren as the Englishman pulled out of a passing move on Fernando Alonso's Ferrari.
The collision took them both off the track and while Hamilton managed to hold on to sixth place, Webber was forced to pit for a new nose cone and finished in ninth place.
Webber, who apologised to Hamilton, was reprimanded by the race stewards for his role in the collision.