Red Bull and Honda protege Yuki Tsunoda topped Formula 2 practice at Monza, one week after taking his maiden F2 feature race victory.
Carlin's Tsunoda, who will drive for AlphaTauri in Formula 1's post-season rookie test in December, set a 1m32.169s halfway through the 45-minute practice session.
This benchmark remained unbeaten with Renault junior Christian Lundgaard coming the closest with a lap 0.058s adrift of Tsunoda's time.
ART Grand Prix driver Lundgaard struggled for pace early in the session but was one of the only drivers to improve in the final 10 minutes.
21-year-old Nikita Mazepin, who lost the Spa feature win to Tsunoda due to a post-race penalty, completed the top three for Hitech GP.
DAMS' Dan Ticktum, who missed last Friday's practice session due to an inconclusive COVID-19 test, set the fourth-fastest time ahead of Ferrari junior Marcus Armstrong - who has not scored a point since the second Red Bull Ring round.
Armstrong's Ferrari stablemates Callum Ilott (UNI-Virtuosi) and Mick Schumacher (Prema) posted the sixth and seventh fastest efforts respectively.
Pedro Piquet was eighth-quickest for Charouz Racing System ahead of Italian series veteran Luca Ghiotto and Williams F1 reserve driver Jack Aitken.
Another Ferrari junior Giuliano Alesi, who crashed exiting the pitlane in practice at Spa, enjoyed a quieter run to set the 11th fastest time of the session.
New championship leader Robert Shwartzman was the slowest of the five Ferrari juniors in 12th place for Prema, over seven-tenths off Tsunoda's time.
Red Bull junior Juri Vips, who is participating in his second F2 weekend with DAMS, was 15th fastest.
Trident's Roy Nissany, fresh from setting a lap time faster than four-time F1 champion Sebastian Vettel in his second F1 free practice outing for Williams, recorded the 18th quickest time in F2 practice.
There was a brief virtual safety car period with just over 20 minutes of the session remaining when Campos Racing's Guilherme Samaia pulled off the circuit on the exit of the first chicane with smoke billowing out of the rear of his car.
David Schumacher, who switched to Carlin from Charouz last weekend at Spa, topped FIA Formula 3 practice on Friday morning.
Points leader Logan Sargeant set the fourth-fastest time while his main title rival Oscar Piastri could only manage 21st in the sister Prema-run machine.
Monza F2 - practice results
|2||Christian Lundgaard||ART Grand Prix||0.058s|
|3||Nikita Mazepin||Hitech Grand Prix||0.063s|
|5||Marcus Armstrong||ART Grand Prix||0.353s|
|7||Mick Schumacher||Prema Racing||0.468s|
|8||Pedro Piquet||Charouz Racing System||0.483s|
|9||Luca Ghiotto||Hitech Grand Prix||0.526s|
|10||Jack Aitken||Campos Racing||0.557s|
|11||Giuliano Alesi||BWT HWA RACELAB||0.683s|
|12||Robert Shwartzman||Prema Racing||0.748s|
|13||Louis Deletraz||Charouz Racing System||0.760s|
|14||Nobuharu Matsushita||MP Motorsport||0.777s|
|17||Artem Markelov||BWT HWA RACELAB||1.025s|
|20||Felipe Drugovich||MP Motorsport||1.296s|
|22||Guilherme Samaia||Campos Racing||1.921s|