Assessing his Formula One team's patchy form before Imola, Schumacher recognised mistakes had been made but believed the last race was a more accurate reflection of Ferrari's championship potential.

• European Grand Prix facts and figures

"We weren't up to the mark a couple of times, that's true, and we were wrong about our choice of tyres once," the seven-times world champion said on his website.

"But in general, the performance we showed at Imola is what Ferrari is capable of now.

"I don't think it will be like last year, when Imola was just a brief ray of light -- nor like the year before that, when we were the dominant force," added the German.

"I think we will be able to show a performance close to that at Imola all year, even though it may vary depending which circuit the race is at."

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Sunday's European Grand Prix at the Nuerburgring is Schuamcher's home race, the closest circuit to his boyhood home in Kerpen, and he expected to be challenging for victory there as well.

"We should be competitive again, and naturally I will do my very best there," said the 37-year-old, who has yet to decide whether to continue racing beyond the end of the year.

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Schumacher's win at Imola was his first since the six-car U.S. Grand Prix fiasco of June last year, a truly hollow victory, and his first 'real' triumph since October 2004 when he won 13 of the 18 races.

However Ferrari also went well at Imola last year, with Schumacher hounding Renault's eventual champion Fernando Alonso [Images] over the final laps in what proved to be the Italian team's strongest race of the season.

The roles were reversed this year, with Schumacher winning the April 23 race at Ferrari's home circuit, but the Nuerburgring could see the advantage swing back again to Michelin-shod champions Renault, McLaren and Honda.

Ferrari use Bridgestone tyres.

"Overall, I think the advantage will remain with Michelin this year," said Renault technical director Bob Bell.

"Ferrari are clearly very quick, and you can never write off Michael or the team. They will be pushing us all year long. But from the next races, I expect the balance to swing back in Michelin's favour."

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