Daniel Abt topped the first day of GP3's post-season test at Valencia, eventually ending more than 0.6sec clear of the rest of the field.
The Lotus ART driver was the first man to break the 1m40s barrier in cold early conditions, and then moved comfortably clear of his opposition when he bolted on fresh rubber as the day drew to a close.
Jenzer Motorsport's Patric Niederhauser ended the day second fastest but 0.636sec in arrears, with Victor Guerin (Lotus ART) and Conor Daly (Carlin) also able to get within seven tenths of Abt's benchmark.
GP3 regular Matias Laine (Marussia Manor) was one of the first drivers to switch to slicks in the morning and was also on top for much of the afternoon, although he fell to fifth by the day's end.
Marlon Stockinger completed a strong day for Lotus ART, who won both the drivers' and constructors' titles this season, by finishing sixth fastest ahead of Tio Ellinas (Marussia Manor).
MW Arden's Will Stevens and Maxim Zimin, and Status GP's Tom Blomqvist all had spells at the top of the times but finished the day in eighth through 10th.