Ocean Racing Technology have started their Istanbul weekend in fine form by filling the top two spots in this morning's free practice session, with Alvaro Parente (right) leading his teammate Karun Chandhok by half a second, while championship leader Romain Grosjean was a tenth further back in third spot.

The Portuguese driver set his best lap of 1:35.347 with ten minutes remaining, but yellow flags late in the session meant his competitors had to deal with a number of yellow flag areas and were unable to close up a time that is already half a second faster than the corresponding lap from last year's free practice.

The session, which took place in blazing sunshine, opened with a competition for the top spot between Alberto Valerio, Jerome d'Ambrosio and Luca Filippi, with the Italian looking to have the session under control after Dani Clos spun off at the turn 8 complex but remained in his car, causing a yellow flag period for the next 10 minutes.

But Parente was the first to use the clear track on fresh rubber to set a time which was to prove untouchable after Diego Nunes found the barriers at turn 4 and Grosjean narrowly avoided a stationary Edoardo Mortara in the gravel trap one corner earlier.

Behind the top three on the timesheets were Valerio, Filippi, Andreas Zuber and Lucas di Grassi, all of whom will be hoping to find a clear track in a few hours time during qualifying so they can give the Ocean pair a run for their money.