Sebastian Vettel was fastest in final practice for the Italian Grand Prix on Saturday but Mercedes's Formula One leader Lewis Hamilton closed the gap and split the two Ferraris on the timesheets.
Vettel lapped with a best time of one minute 20.509 seconds, 0.081 quicker than Hamilton, with the sun coming out after morning rain at Monza.
The German did his run earlier in the session than Hamilton.
Ferrari's Kimi Raikkonen was third fastest, 0.173 off the pace, with Valtteri Bottas fourth for Mercedes ahead of what is likely to be a battle between the two front-running teams for pole position.
Red Bull's Max Verstappen was fifth fastest.
Hamilton, 17 points clear of Vettel with eight races remaining, has been on pole at Monza for the past four years while Mercedes are unbeaten there in the V6 turbo hybrid era that started in 2014.
However Ferrari's hopes of a first home win since 2010 are high after Vettel triumphed in Belgium last weekend with a car that clearly had the measure of the Mercedes.
He was also fastest on Friday at Monza in a one-two with Raikkonen.
Both Hamilton and Vettel have five wins each in a season likely to see one of them crowned as a five-times world champion.
Sauber's Swedish driver Marcus Ericsson returned to action after a huge crash on Friday that had his mechanics breaking the overnight curfew to get the car rebuilt in time.
Ericsson is likely to have to take a grid penalty as a result of engine changes made.