Michael Schumacher [Images] warned his rivals not to write him off despite his failure to finish Sunday's season-opening Australian Grand Prix.

The seven-times world champion made his worst ever start to a Formula One season when he qualified 18th then retired 15 laps before the end after colliding with Nick Heidfeld [Images].

But the 36-year-old German said there were mitigating circumstances behind his poor showing at Albert Park and he was still optimistic about his chances of defending his world title.

"There are some positives to take away from this race," he said. "We can be satisfied and regard this weekend as a good sign for the rest of the championship."

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Schumacher's poor showing was in stark contrast to last year when he led his rivals on a virtual procession to win the Australian Grand Prix for the fourth time in five years, paving the way for him to capture his seventh championship.

Everything went perfectly then but luck did conspire against him this time.

He arrived in Australia with last year's Ferrari [Images] because his new car was not ready and his qualifying run was ruined by a torrential rain storm.

Despite starting from the back row of the grid, Schumacher still managed to weave his way through the field to reach seventh position two-thirds of the way through the race when misfortune struck again and he was hit from behind by Heidfeld's flying Williams.

NO BLAME

The pair spun off the track and although Schumacher got himself back on the circuit his chances of finishing in the points were over and he nursed the car back to the pits and into the garage.

"My car was slightly damaged in the collision and there was no point in going on," Schumacher said.

"It is impossible to blame either of us. I saw him behind me just as I came out of the pits and I made it clear I was defending my position.

"At one point I lost sight of him in my mirrors and went into the corner when I felt I'd been hit. I can't blame him for trying to overtake me."

The mood among the rest of the Ferrari team was also buoyant after Schumacher's Brazilian team mate Rubens Barrichello finished second from an 11th place start.

"It shows that Ferrari has no crisis. We're here, we're going to fight," Barrichello said.

"It's still our old car and the new car is going to give us even more pleasure."

However, Ferrari team boss Jean Todt issued a word of caution, saying the opening race had shown that the Italian manufacturer was not going to get everything their own way this season.

"The first weekend of the season ends with mixed emotions," Todt said.

"Today's result confirms our prediction that it will be a very closely contested championship."

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