Mika Hakkinen last night vowed to keep the fight for the World Championship clean - and upped the pressure on title rival Michael Schumacher to do the same.

The Finn has seen his one-time 22 points advantage over Schumacher whittled down to nothing, leaving the duo facing a two-race duel starting with Sunday's Luxembourg Grand Prix at the Nurburgring in Germany. But he insisted there will be no dirty tactics from him or McLaren Mercedes team-mate David Coulthard despite facing the prospect of seeing a first drivers' crown snatched from his grasp. Hakkinen left Schumacher in no doubt that he should not even contemplate attempting any dirty tactics or ask his fellow Ferrari driver Eddie Irvine to do so. "I would never ask my team-mate to take another driver out for me. The thought has never crossed my mind. That sort of thing wouldn't." The eyes of the world will be on Schumacher over the next two races following the callous and calculating way he tried to take Jacques Villeneuve out in their title decider last season.