Davide Valsecchi waited until the very last minute to take the top spot in today's free practice session in Istanbul, claiming the fastest lap as the clock ran out on the session to inch ahead of Giedo van der Garde and Michael Herck.

The Italian had been in the top ten, but not quite at the front, throughout the session, but a late pit stop for a tweak gave him the edge to run a time of 1:36.021 to put himself just 0.058 ahead of the Dutchman in an incredibly tight session, which saw 16 drivers all run a time within a second of the top spot.

The conditions seemed to bring out the fighting nature of the field, with the competition fierce from the outset: every lap saw the lead time change a number of times as they gauged away at each other's best efforts on their first set of tyres.

With temperatures soaring throughout the session, the second half saw an increase in off-track activity, with Giacomo Ricci blotting his copybook when he spun and stalled at the hairpin on the back straight, but he was not alone as most of the field ran wide or missed a braking point at some stage on the undulating circuit.

Addax thought they'd done enough until Valsecchi popped up at the end with his best effort, but there was nothing in the times as Sam Bird, Sergio Perez, Dani Clos (who overcame a mechanical problem for most of the session to bring home a decent time when he finally got out), Christian Vietoris and Adrian Zaugg line up just behind the top three, promising a battle royale for this afternoon's qualifying session.