Yu Kanamaru recorded the fastest time on the conclusion of Barcelona's two-day pre-season Formula V8 3.5 test on Wednesday
Series newcomer Teo Martin Motorsport shone, as Kanamaru's morning effort of 1m29.951s, the quickest time of the test, was backed up by team-mate Matevos Isaakyan topping the slower afternoon session.
Russian Isaakyan, who will race for Koiranen in GP3 this season, ended the day 11th overall on combined times.
"We saved the new tyres for this morning, but a red flag did not allow me to complete a perfect lap," said Kanamaru, who recorded his time late in the morning before teams switched attention away from single-lap pace.
"I feel really confident in this team," Kanamaru continued.
"I know most of the personnel from my previous team [Euroformula Open outfit Emilio de Villota Motorsport].
"This situation allows me to focus on my first full season in this discipline. So far I can't complain."
Arden's Tuesday pacesetter Aurelien Panis took second, 0.191s adrift, while single-seater veteran Tom Dillmann in third was a constant factor towards the top of the timing screens.
Briton Emil Bernstorff, who has yet to confirm his 2016 racing plans, was fourth fastest for Strakka ahead of Renault Driver Academy-backed Louis Deletraz.
Fortec driver Deletraz was the first driver to improve on Panis's Tuesday benchmark in the morning session, which was red-flagged when Giuseppe Cipriani and former GP2 race winner Johnny Cecotto Jr were involved in an incident.
RP Motorsport's Cecotto was second fastest in the afternoon, and hinted that he could race in the category this year.
"It's a great car to drive," said Cecotto. "It's very quick, especially in the high speed corners, and with the Michelin tyres it's also nice in the slower speed corners.
"From the first moment [with RP] we were quite close to the leaders, and it's great to feel competitive.
"We have to wait, this should be my number one programme, [it is] my target..."
Last year's Formula Renault 3.5 runner-up Matthieu Vaxiviere was third quickest and unworried after finishing ninth overall for SMP Racing.
"We are trying to improve our set-up a lot," said Vaxiviere.
"This is just testing, and we need to work to get ready for the first qualifying in Motorland.
"We do not need to be in P1 and fit new tyres at the same time as everybody else.
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