French duo Norman Nato and Pierre Gasly topped the two respective sessions of the first day of GP2's final pre-season test at Jerez.
Nato headed Red Bull junior Gasly by just 0.15s in the morning session that had been briefly interrupted by fog - and while Gasly clocked in the fastest time in the afternoon, Nato's lap stood as the best overall from the day.
Switching from Arden to Racing Engineering for 2016, Nato took over at the top of the timesheets in the closing stages of the first session, him and Gasly the only drivers to go below 1m25s.
Jordan King, also of Racing Engineering, was third, ahead of compatriot Alex Lynn and top rookie Antonio Giovinazzi.
Mitch Evans, Sergey Sirotkin, Arthur Pic, Oliver Rowland and Gustav Malja completed the top 10, with Raffaele Marciello and Daniel de Jong the final two drivers within a second of Nato in 11th and 12th.
The afternoon then featured the exact same top five, albeit in a different order.
Gasly and former teammate Lynn then set the pace in that session, with Racing Engineering duo Nato and King third and fifth, split by Giovinazzi.
An overall 21 cars took to the track on Tuesday, with Carlin running just one car for its sole confirmed driver Marvin Kirchhofer and Status skipping the test entirely.
Day 1 results
|1||Norman Nato||Racing Engineering||1:25.811||1:26.558|
|2||Pierre Gasly||Prema Racing||1:25.961||1:26.375|
|3||Jordan King||Racing Engineering||1:26.124||1:26.617|
|5||Antonio Giovinazzi||Prema Racing||1:26.322||1:26.556|
|6||Mitch Evans||Jagonya Ayam Campos||1:26.350||1:27.222|
|7||Sergey Sirotkin||ART Grand Prix||1:26.405||1:27.275|
|10||Oliver Rowland||MP Motorsport||1:26.674||1:27.101|
|12||Raffaele Marciello||Russian Time||1:26.762||1:26.989|
|13||Daniel de Jong||MP Motorsport||1:26.805||1:27.734|
|15||Jimmy Eriksson||Arden International||1:26.888||1:28.352|
|16||Artem Markelov||Russian Time||1:27.065||1:27.487|
|18||Nobuharu Matsushita||ART Grand Prix||1:27.273||1:27.224|
|19||Sean Gelael||Jagonya Ayam Campos||1:27.421||1:27.824|
|20||Philo Paz Armand||Trident||1:28.744||1:27.838|
|21||Nabil Jeffri||Arden International||1:28.193||1:27.846|