Lawrie, who two weeks ago lost a play-off for the Czech Open to Swede Peter Hanson, had made the halfway cut with nothing to spare at one under par.
But eight birdies in his last 13 holes gave the 36 year old Dubliner the lowest round of his European Tour career and lifted him all the way from 61st to fifth on nine under.
The overnight leaders were only just setting off, however, and Spaniard Miguel Angel Jiménez, whose second round 61 was his career best, immediately birdied the long first to move to 15 under.
Ryder Cup team-mate Edoardo Molinari, going for his second successive victory, matched it to remain three behind, but 17 year old fellow Italian Matteo Manassero had to be content with three opening pars and was four back in third spot.
Lawrie climbed to third when Manassero bogeyed the fourth and fifth and Finn Mikko Ilonen made a poor start as well.
But Jiménez went four clear of Molinari - yet to have a bogey all week - when he made his second birdie of the day on the fifth.
Molinari birdied the seventh and eighth, but did not cut into Jiménez's lead with either of them as the 46 year old from Malaga made five footers both times.
Remarkably, Manassero birdied the same two holes as well to repair the earlier damage and get back into third place on 11 under. But he was seven adrift of Jiménez.