Sirotkin heads Gasly and Lynn on Day 1 of Barcelona test

Sirotkin was quickest in the morning session, and his time would subsequently stand unbeaten for the rest of the day due to the arrival of rain.

Prema Powerteam's Pierre Gasly was runner-up in session one after being dethroned by Sirotkin in the last half-hour, despite subsequently posting a late improvement of his own.

This, however, allowed the Red Bull junior to remain ahead of former teammate Alex Lynn, the Williams development driver finishing 0.099s adrift of Sirotkin.

Best of the rest, almost half a second behind the pacesetter, was Norman Nato, with his Racing Engineering teammate Jordan King in sixth and the duo split by Campos driver Mitch Evans.

And with Arthur Pic completing the top seven, the highest-placed rookie of the session - Prema's Antonio Giovinazzi - was only eighth.

In the afternoon, the track was drenched by rain that had begun a few minutes minutes prior to the beginning of the second session, making it virtually impossible for anyone in the field to post an improvement.

On a drying track, it was Russian Time's Raffaele Marciello who went quickest by more than a second and a half, heading DAMS driver Nicholas Latifi and GP3 runner-up Luca Ghiotto, who will make his GP2 debut with Marciello's former team Trident.

On Day 2, Status Grand Prix will enter the fray with the duo of Sergio Canamasas and Meindert van Buuren, with one further change in the rest of the field - Rene Binder replacing Will Buller at Carlin.

Day 1 results:

Pos.	Driver	Team	AM	PM
1	Sergey Sirotkin	ART Grand Prix	1:29.072	1:44.905
2	Pierre Gasly	Prema Racing	1:29.141	1:45.559
3	Alex Lynn	DAMS	1:29.171	1:43.909
4	Norman Nato	Racing Engineering	1:29.542	1:48.175
5	Mitch Evans	Campos Racing	1:29.655	1:45.274
6	Jordan King	Racing Engineering	1:29.686	1:44.888
7	Arthur Pic	Rapax	1:29.737	1:49.035
8	Antonio Giovinazzi	Prema Racing	1:29.771	1:46.455
9	Sean Gelael	Campos Racing	1:29.784	1:48.513
10	Nobuharu Matsushita	ART Grand Prix	1:29.934	1:46.675
11	Luca Ghiotto	Trident	1:29.967	1:43.758
12	Daniel de Jong	MP Motorsport	1:30.004	1:50.630
13	Nicholas Latifi	DAMS	1:30.072	1:43.500
14	Artem Markelov	Russian Time	1:30.139	1:48.686
15	Raffaele Marciello	Russian Time	1:30.289	1:41.863
16	Marvin Kirchhofer	Carlin	1:30.317	1:45.986
17	Gustav Malja	Rapax	1:30.396	1:44.176
18	William Buller	Carlin	1:30.752	1:46.257
19	Oliver Rowland	MP Motorsport	1:31.274	1:45.889
20	Philo Paz Armand	Trident	1:31.583	1:47.345
21	Jimmy Eriksson	Arden International	1:32.195	1:46.043
22	Nabil Jeffri	Arden International	1:32.773	1:47.692