FIA Formula Two Championship points leader Luciano Bacheta continued his pacesetting form at the pre-event test at Spa-Francorchamps ahead of the fourth race weekend of the season at the Belgian circuit.
The 22-year-old from Romford made the most of dry conditions in the second of five sessions during a rain-affected day of running.
The day started on a dry circuit, with Christopher Zanella heading the first session with a time of 2m08.227s to go half a second clear of Mihai Marinescu.
The second session saw Bacheta improve the benchmark to a 2m07.463s, which would remain unbeaten with the afternoon running hit by rain.
Bacheta edged out Alex Fontana in that session by just 0.076s, with Fontana's fellow Swiss driver Matheo Tuscher finishing up third.
39-year-old Bulgarian Plamen Kralev finished the day an unexpected fourth fastest after finishing 0.750s behind Bacheta in that second session.
That put him just ahead of Zanella's session one benchmark in the day's final classification with Marinescu and Daniel McKenzie sixth and seventh.
Parthiva Sureshwaren went sixth fastest in session two to end the day eighth, with Max Snegirev ninth and Markus Pommer tenth.
Pommer was the fastest of only four drivers to set a time during the third session when conditions were too wet for slicks but not wet enough for wet tyres. Marinescu was quickest in the wet fourth session ahead of Kevin Mirocha and Tuscher, before Bacheta topped the final session on a drying track.
Series newcomer Vittorio Ghirelli was third fastest in that final session.