to view the full Thursday AM results.
Sauber man, Sergey Sirotkin, ended a morning test session fastest for the second time this week.
The Russian led throughout but his times were challenged by the experience of Nikolay Martsenko and Zoel Amberg who were placed second and third fastest respectively.
Red Bull Junior, Pierre Gasly was the highest place rookie in fourth, six tenths-of-a-second behind Sirotkin. Pietro Fantin failed to make the top five for the first time this year; he sat sixth behind the new circuit record-holder, Carlos Sainz Jr.
Matias Laine, Norman Nato, Marlon Stockinger and his Lotus team-mate, Matthieu Vaxiviere completed a familiar top ten.
Drops of rain later in the session did cause some drivers to struggle; Sainz Jr stopped at turn 13 whilst Meindert Van Buuren had a run in with the gravel at turn 2.
Marco Sorensen did not post a time after stopping on track.
One more afternoon test in Aragon remains.