MONZA, Italy — Formula One world champion Lewis Hamilton set the pace in practice for the Italian Grand Prix Friday with dominant Mercedes turning on the power and leaving their rivals trailing. The Briton, who will be chasing his 11th pole position in 12 races on Saturday, told reporters on arriving at Monza with his hair dyed blond that he was going through an ‘experimental' phase. There was nothing radically different in his track performance, however, only clear evidence that the upgraded Mercedes power unit was faster than ever. The championship leader, 28 points clear of closest rival and teammate Nico Rosberg with eight races remaining, lapped nearly half a second faster than the German in sunny morning conditions. The Briton, winner of six races so far this season, was only 0.021 quicker than Rosberg in the afternoon, when he produced his fastest lap of one minute 24.279 seconds on the quickest track on the calendar. Ferrari's Sebastian Vettel, preparing for his first Italian race in the home team's red overalls, was third quickest in both sessions — a massive 1.588 slower than Hamilton in the morning and 0.759 adrift after lunch. That will have come as a disappointment for the fervent local fans, displaying the usual array of Ferrari banners in the stands including several supporting stricken favorite Michael Schumacher and the late Jules Bianchi. Mercedes-powered Force India was fourth in both sessions, with Nico Hulkenberg in the morning and Sergio Perez in the afternoon. The opening session was halted briefly when Spaniard Carlos Sainz lost control of his Toro Rosso at Parabolica and skidded into the gravel, bringing out the red flags at the half hour mark. Honda-powered McLaren, stacking up more grid penalties for engine changes to both Fernando Alonso and Jenson Button's cars, endured difficult sessions with the Briton 18th and 19th respectively. There were no problems with the Pirelli tires after alarming high-speed blowouts in Belgium two weeks ago. Not for the first time, Bernie Ecclestone exerted his authority over Formula One and the sport's leading drivers with a few forthright words when he intervened to defuse a simmering row over the quality of Pirelli's tires. He also gave a clear signal of possible intent and assured the Italian company not only has security and backing during a difficult period, but, another long-term deal with the sport in prospect. After hearing of continuing complaints from four-time champion German Sebastian Vettel of Ferrari, whose expletive-riddled anger had been aired widely after last month's Belgian Grand Prix, the sport's commercial boss issued a rare official public statement. This said: “Pirelli has been a first class partner of Formula 1 during the five seasons in which it has been the official supplier of tires to the FIA Formula 1 world championship. “We continue to have full confidence in the safety, quality and suitability of its tires. Within the constraints of safety considerations, which are always paramount, Formula 1 encourages Pirelli to provide tire compounds with performance because tire degradation contributes to the challenge and entertainment of a Formula 1 race. “When doing so, Pirelli provides strong guidance to competitors about any performance limitations of the tires supplied. “Competitors should heed Pirelli's expert advice when setting their race strategy and tactics, and if they do not, it is at their own risk. “We are entirely satisfied Pirelli was not at fault for any tire-related incidents during the Belgian Grand Prix.” — Agencies