Max Verstappen rebounded from Red Bull's lost time on Friday to set an impressive pace over the field in a final practice session that continued the action-packed start to the Emilia-Romagna GP.
The Dutchman, F1's polesitter at the Bahrain season-opener three weeks ago, was four tenths of a second clear of a chasing pack led unexpectedly by McLaren's Lando Norris.
Lewis Hamilton was 0.557s adrift in the lead Mercedes, with Sergio Perez close behind in fourth in the second Red Bull.
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It remains to be seen whether Verstappen and Red Bull will carry that level of superiority into qualifying, which begins at 1pm live on Sky Sports F1, but the combination did beat Mercedes to pole by 0.4s in Bahrain.
In cold conditions in Italy, drivers continued to regularly run wide around the narrow and challenging Imola track with the best lap times often achieved on a car's second timed lap out of the pits.
Lap times were also regularly deleted by race control for track limits violations, despite the rules being eased at Turn 13 ahead of Saturday's running.
Williams' Nicholas Latifi was the only driver to crash, spinning off and tapping the barriers with his car's front wing at Turn Three, but the team were still able to get the Canadian back out on track for the closing minutes.
Antonio Giovinazzi, Pierre Gasly and Valtteri Bottas were among the many drivers to run wide off track.
Sky F1's Damon Hill, a two-time race winner at Imola, said: "I've never seen so many cars leaving the track. They're all really tricky corners, you have to be precise as possible - otherwise you're in trouble."
Ferrari have looked strong on home soil so far and finished fifth with Charles Leclerc and seventh with Carlos Sainz, the two red cars split by the perennially impressive Pierre Gasly for fellow Italian outfit AlphaTauri.
Mercedes' Bottas, who had lap times deleted, was down in eighth ahead of the two Alpine cars, as Fernando Alonso and Esteban Ocon both sneaked into the top 10 late in the hour.