
Italian Trulli registered a fastest time of 1 minute 20.801 seconds for the 4.655-kilometre circuit. Red Bull's David Coultard was second fastest, 0.457 seconds slower, with Nico Rosberg third fastest in a Williams.
Lewis Hamilton, who was fastest on the first two days of testing, had to be satisfied with 10th quickest in his McLaren-Mercedes, one place behind world champion Kimi Raikkonen of Ferrari.
The first race of the new F1 season, the Australian Grand Prix, takes place on March 16 in Melbourne.