Lewis Hamilton clocked the fastest lap by the narrowest of margins to top the times in Saturday morning's final free practice session ahead of Sunday's Italian Grand Prix.
The 27-year-old Briton, who was quickest in Friday afternoon's practice, produced a best time of 1min 24.578sec in his McLaren, outpacing nearest rival and local hero two-time champion Spaniard Fernando Alonso of Ferrari by just 0.001 seconds.
Hamilton's stunning effort came just four minutes from the end of the final hour's work before qualifying on another beautiful late summer's day at the old Autodromo Nazionale where the air temperature was 27 degrees and the track temperature was 36 degrees Celsius.
Briton Paul Di Resta was third fastest, two-tenths adrift of the fastest pair, in his Force India car ahead of Brazilian Felipe Massa in the second Ferrari, Hamilton's team-mate Jenson Button - coming off victory in Belgium - and German Nico Rosberg of Mercedes.
The times of the leading drivers endorsed Hamilton's overnight view that qualifying is expected to be a very closely-contested affair with McLaren and Ferrari fighting for pole in contention with Mercedes.
Finn Kimi Raikkonen was seventh quickest ahead of the second Force India driven by German Nico Hulkenberg, whose name has been linked with a possible move to Ferrari, Mexican Sergio Perez of Sauber and Venezuelan Pastor Maldonado of Williams.
Maldonado, involved in a series of incidents this season, was wearing a new helmet design with a slogan that proclaimed 'Less Trouble More Speed'.
He enjoyed an incident free session as the field concentrated on perfecting their set-ups in stable, dry and near-perfect conditions, only the two stars of German motor racing suffering problems.
Seven-time champion Michael Schumacher, 43, had problems with the Kinetic Energy Regeneration System (KERS) on his Mercedes car.
Defending champion Sebastian Vettel of Red Bull slowed to a halt with 'no battery' on his way to 12th, one place behind team-mate Australian Mark Webber. Schumacher was 14th. Vettel wound up eight-tenths off the pace set by Hamilton.
The Red Bulls appeared to be struggling with finding the speed for a single fast lap while Ferrari, enjoying support from their home fans, appeared to revel in the chance to take turns in following each other, one driver gaining from the tow of his team-mate to set an improved time.
It is a tactic that the team may consider using in qualifying.