Davide Valsecchi was out on his own at the top of the Friday morning practice timesheets, his laptime of 1:41.417s over two thirds of a second faster than the closest competition provided by Carlin's Max Chilton and Barwa Addax's Johnny Cecotto Jr.
Valsecchi's DAMS team mate Felipe Nasr was also on good form, initially beating Valsecchi's first flying lap time by a couple of tenths before the Italian put on the afterburners in the middle of the 30-minute session to go well ahead of everyone, and to stay there for the remainder of practice.
Early laps proved tricky as drivers got to know the circuit, which for many of them was the first time they had raced in Bahrain after last year's GP2
Asia event was cancelled at the last minute due to the political unrest that is still a concern to the teams this weekend.
Several drivers slipped off the track in the initially dusty and sandy conditions, with Lotus GP's Esteban Gutiérrez having a particularly difficult time of keeping it on the island while still managing the seventh fastest time of the session, albeit 1.232s off the leader.
Many drivers improved their times in the second half of the session after a brief interval in the pits, although no one challenged Valsecchi at the top. However, an odd miscommunication between team and driver meant that Valsecchi was held in pit lane and then released when it was too late for him to return back out on track, leaving him stuck by the red light at the end of pit lane as the session wound down following the chequered flag.
There were no major incidents, although Rapax's Tom Dillmann brought out a lengthy local yellow when his car lost drive and ground to a halt through turn 1. His time put him in 24th place, which was still one spot ahead of his team mate Ricardo Teixeira
Arden's Simon Trummer also had a problem on an early lap, but he was able to limp home to the pits and eventually re-emerged to set the 16th fastest time of the session, although still a second off his team mate Luiz Razia who ended up in fifth place in the timesheets for the morning. However on his cool-down lap, Razia nearly wandered into the path of a flying Nasr and had to apologise for a scary near-miss.
There were two driver changes confirmed for this weekend, with Dani Clos taking over from Josef Kral at Barwa Addax and Brendon Hartley a last-minute replacement for Jon Lancaster at Ocean Racing. Clos finished in 9th place and Hartley was down in 22nd by the time the session ended.Full practice session times available