The world championship leader Eddie Irvine tried to increase the psychological pressure on his rival for the drivers' title yesterday warning Mika Hakkinen not to attempt anything improper in the deciding Japanese Grand Prix at Suzuka on Sunday.

Three days after Irvine's Malaysian Grand Prix victory was restored in a Paris court of appeal, the Ulsterman said he was ready for any "dirty tricks". He believed the Finn and his McLaren team-mate David Coulthard might "play games and push me back into the clutches of the Stewarts, Williams and Jordans. It could cause problems and we have got to be very careful. We cannot afford to relax".

The irony of his remarks will not be lost on Hakkinen and the McLaren team. During the Malaysian Grand Prix, Irvine's Ferrari team-mate Michael Schumacher spent the opening laps of the race deliberately attempting to slow up Hakkinen so he would be caught by the Stewarts of Johnny Herbert and Rubens Barrichello.

Arriving in Japan, Irvine added that he would benefit from his local knowledge of Suzuka, a circuit on which he raced Formula 3000 cars regularly from 1991 to 1993.

"Suzuka is my favourite circuit," he said. "It's like my home grand prix because I raced in Japan for three years. I had a lot of fun here."

But Hakkinen also has a superb track record at Suzuka. In 1993 he finished third there on only his second drive for McLaren behind team-mate Ayrton Senna and Alain Prost's Williams. In 1995 he finished second behind Michael Schumacher's Benetton three weeks after having his appendix removed, while in 1998 he clinched his first world championship title there with a flag-to-flag success.

Despite this, Irvine knows that Hakkinen - four points behind him in the championship - has the odds stacked against him.

Ferrari's strategy will again make use of Michael Schumacher's presence in the second Ferrari F399. The German driver will probably go all out for a win with Irvine sitting behind Hakkinen in third or fourth place, to win the championship by one or two points.

"That will be nice," speculated Irvine. "If Mika breaks down at the start, then I can really have fun because I really love the circuit. It will be the greatest way to go into the race and I can go crazy."