Monza (Italy), Sep 3 (IANS): Lewis Hamilton showed top form as he dominated the final practice session at the Italian Grand Prix for Mercedes here on Saturday.

The world champion was 0.393 seconds quicker than teammate Nico Rosberg, with Ferrari's Sebastian Vettel 0.938 seconds off the pace in third place.

Mercedes have a huge advantage over Ferrari, who have a smaller but clear edge over Williams and Red Bull.

Williams' Valtteri Bottas and Felipe Massa were next, ahead of Red Bull's Daniel Ricciardo and Max Verstappen.

Hamilton, fresh from his scintillating effort in finishing third from the back of the grid in Belgium last weekend, was in imperious form throughout the final hour of practice at Formula One's most historic circuit. He was just under 0.2 seconds clear of Rosberg in second practice on Friday and doubled that margin on Saturday morning.

Even at this early stage, the race victory looks likely to be a private battle between Hamilton and Rosberg, with Ferrari nowhere near the world champions despite introducing their final engine development upgrade of the season in an attempt to close the gap.

Hamilton is nine points clear of Rosberg heading into the grand prix, with eight races remaining this season.

Ferrari are also said to have some concerns about the reliability of the new engine, having rushed it through to introduce it in time for their home race.

Force India's Sergio Perez was ninth, ahead of Haas' Esteban Gutierrez, whose teammate Romain Grosjean had a spin early in the session and was beached in the gravel trap at the Ascari chicane.