Boccolacci, who drove for Trident but is still yet to be confirmed to be racing with the Italian squad in GP3 this year, was a tenth in the clear in the morning session.

His time of 1m21.191s was almost four tenths quicker than Alessio Lorandi's earlier benchmark, the Italian leading the way for most of the final hour of the practice.

Jack Aitken was the lead ART Grand Prix driver in second, beating teammate and compatriot George Russell by two hundredths.

Russell went on the top the afternoon session, but his time was almost six tenths off Boccolacci's earlier effort.

Anthoine Hubert was the third ART in the day's overall top four, while the French team's final driver Nirei Fukuzumi was only 10th.

Ryan Tveter, who is testing with Trident but, like Boccolacci, is yet to be announced for the season, was fifth.

The American driver was 0.005s quicker than Marcos Siebert, with Jenzer duo Lorandi and Arjun Maini also not far behind.

Haas protege Santino Ferrucci was the top DAMS car in ninth.

Day 1 results