THE WILLIAMS team's official announcement yesterday that Heinz Harald Frentzen would be taking over Damon Hill's job next season not only confirmed what many in Formula One had expected for weeks, but also triggered the prospect of a spectacular `grudge match' for the 1997 world championship.

Yet the focus of Frentzen's competitive energy will not just be directed at his Williams team mate Jacques Villeuve. His real target seems certain to be his compatriot, Michael Schumacher, who has been his fiercest personal rival for many years, both on and off the race.

Not only did Frentzen's former girlfriend Corinna Betsch leave him to marry Schumacher, but the 29 year old from Moenchengladbach has spent the last three years struggling with an uncompetitive Sauber while - his rival monopolised the limelight - in 1994 he became the first German driver to win a world championship and retained the title the following year.

Armed with a Williams Renault, Frentzen now feels he, can repay the compliment and justify a reputation originally forged during his years with Schumacher as a member of the Mercedes sports car racing team back in the late 1980s. In those days Frentzen was regarded as being every bit as quick as Schumacher, but subsequently Schumacher seemed to get all the opportunities to establish the upper hand.

Frentzen's best placing was third place in last year's Italian Grand Prix at Monza, while this year he has finished fourth on two occasions, in Monaco and Spain. He currently lies 10th in the drivers' world championship with six points.

The German's move to Williams means that both members of Eddie Jordan's last Formula 3,000 team now have top line drives in Formula One.

Eddie Irvine partnered Frentzen in the canary yellow Camel Jordan team of 1990, and the Irishman was by far the faster of the two. Frentzen finished 16th in the series while Irvine, in identical equipment, was third overall and scored a race win.

Frentzen's best race result was a fifth place while he crashed no less than seven times from 10 starts. He was a bit prone to accidents, but he had good speed," said Eddie Jordan last night.

Irvine remembers those days well: "I think he used to have trouble coping with the pressure," he said.

It is believed that Frentzen will be paid around £2.5 million a year for his two year contract, a bargain basement deal for Frank Williams, who has probably paid, far less for his new signing and Villeneuve than the £8 million which the displaced Hill was reputedly asking for.