GP2 frontrunner Raffaele Marciello set the pace on the opening day of the series' post-season test at the Yas Marina Circuit in Abu Dhabi.
Marciello, reuniting for the test with the Trident team he had raced for in 2015, was runner-up in the opening session and assumed the lead in the closing minutes of the afternoon run, with a lap of 1m48.937s.
The morning run was headed by ART Grand Prix's Nobuharu Matsushita, the Honda protege posting a 1m49.483s benchmark an hour into the session.
Marciello was second heading into the midday break, with only Artem Markelov – the Italian's regular-season teammate at Russian Time – joining the trio below 1m50s.
Times ramped up quickly in the afternoon, GP3 champion Charles Leclerc and Jordan King surpassing Matsushita's earlier benchmark, although the Japanese driver had gone quicker himself as well and was now top at 1m49.307s.
Shortly thereafter, he was overhauled by Marciello and Nicholas Latifi, the former becoming the first driver in the test to log a sub-1m49s lap.
The Italian would remain unmatched until a red flag caused by a Markelov stoppage ended the day's running early.
Matsushita finished the afternoon session in second, ahead of DAMS pair Oliver Rowland and Latifi, with Johnny Cecotto (Rapax) in fifth matching the Canadian's laptime.
New Prema signing Leclerc was top rookie in sixth, ahead of Russian Time duo King and Markelov, Luca Ghiotto (Rapax) and Sean Gelael.
Series runner-up Antonio Giovinazzi, running alongside Gelael at Arden, was 11th.
Day 1 results
|2||Nobuharu Matsushita||ART Grand Prix||1:49.483||1:49.107|
|6||Charles Leclerc||PREMA Racing||1:50.958||1:49.265|
|7||Jordan King||RUSSIAN TIME||1:50.272||1:49.348|
|8||Artem Markelov||RUSSIAN TIME||1:49.892||1:49.426|
|10||Sean Gelael||Arden International||1:50.594||1:49.709|
|11||Antonio Giovinazzi||Arden International||1:51.033||1:49.813|
|12||Louis Deletraz||Racing Engineering||1:50.922||1:49.854|
|13||Alex Palou||Pertamina Campos Racing||1:50.942||1:49.870|
|14||Alexander Albon||ART Grand Prix||1:51.277||1:49.945|
|15||Gustav Malja||Racing Engineering||1:50.763||1:49.947|
|16||Antonio Fuoco||PREMA Racing||1:50.940||1:50.046|
|17||Philo Paz Armand||Trident||1:51.269||1:50.187|
|18||Egor Orudzhev||Pertamina Campos Racing||1:51.050||1:50.582|
|19||Sergio Sette Camara||MP Motorsport||1:51.509||DSQ*|
|22||Salvatore De Plano||MP Motorsport||1:58.844||1:55.584|
*car found underweight