The Formula Renault 3.5 runner-up, who told AUTOSPORT earlier this month that GP2 was his preference for 2015, contested the final part of this season with Caterham and did not manage to score.
But he has proved unstoppable with champion team DAMS in post-season testing, heading all three days of running at Yas Marina.
Gasly was half a second clear of the field in both Saturday sessions. European Formula 3 champion and Lotus Formula 1 junior Esteban Ocon was second in the sister DAMS car in the afternoon, while Jordan King - testing for MP - had been next best in the morning.
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Both Ocon and King were frontrunners all day, with the Frenchman completing the session one top three and the Briton fourth later on behind already-signed 2015 Campos racer Arthur Pic.
After his try-out with Status on Friday, Ferrari Driver Academy member Raffaele Marciello was back with his 2014 squad Racing Engineering. He was fifth in the morning and ninth in session two.
GP3 champion Alex Lynn completed a week that has encompassed sealing his title, making his F1 test debut with Lotus and sampling GP2 for the first time with Carlin by switching to ART for Saturday.
He was in the top 10 in both sessions, though he caused the final red flag of the year by stopping on track late in the evening.
The day's only other stoppage came when FR3.5 regular Beitske Visser parked her Lazarus car earlier in the day.
Sometime Sauber F1 tester and FR3.5 race winner Sergey Sirotkin had a second day of GP2 running with Rapax and was in the top six all day.
Another man to set an eye-catching time in his first week of GP2 was GP3 frontrunner Dino Zamparelli, who was seventh for Status in the morning.
Mitch Evans was among the GP2 regulars trying different cars. A two-time race winner and fourth in the standings with Russian Time this year, he sampled Racing Engineering's second car on Saturday (pictured above), while Auto GP champion Kimiya Sato occupied Evans's usual seat.
The Campos car Sato has raced in GP2 this year was handed over to Rio Haryanto, who was fourth in the morning.
Session one:
Session two:
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