GP3 Barcelona: Luca Ghiotto leads Trident 1-2 in practice

The Italian displaced team-mate Oscar Tunjo from the top of the timesheets by just 85-thousandths of a second in the closing stages of the session.

The Trident drivers were among a flurry of late improvers, with Matheo Tuscher also jumping up to third for Jenzer Motorsport.

Long-time session topper Esteban Ocon, the reigning European F3 champion who moves sideways into GP3 this year with ART Grand Prix, ended up fourth fastest, three tenths down.

Behind him was Ferrari-contracted Antonio Fuoco, who was outside the top 10 until he leaped to fifth place late on.

This relegated Alex Palou, who finished third in Euroformula Open last year, to seventh ahead of another of the late improvers, Ralph Boschung.

Mitch Gilbert was eighth fastest ahead of Jimmy Erikssen, the latter not setting a serious laptime until some way into the session and then becoming frustrated with traffic.

Alex Fontana rounded out the top 10, almost a second off the pace and just ahead of Jann Mardenborough, who briefly topped the times early in the session.

The session was twice interrupted by red flags, the first triggered by Kevin Ceccon's Arden machine grinding to a halt.

Later, Marvin Kirchhofer, who ended the session 12th, went off at Turn 3 and had to be retrieved from the gravel.