Jose Maria Lopez set the fastest time on the first morning of the World Endurance Championship Prologue test at Barcelona, leading a Toyota one-two ahead of Sebastien Buemi.
On a sweltering morning at the Circuit de Barcelona-Catalunya, Kamui Kobayashi laid down a benchmark of 1m30.906s in the first two hours of the morning session in the #7 Toyota TS050 HYBRID.
That time stood until the final hour, when Lopez broke the 90-second barrier with a 1m29.991s - 0.267 seconds up on the best time set in the sister #8 car by Buemi.
Rebellion, which is running two cars at Barcelona despite only having confirmed one for the Silverstone season opener, was the best of the privateer squads in third and fourth.
Gustavo Menezes set the team's best time of 1m31.603s in the #3 Rebellion R-13, 1.612s off the pace, while Bruno Senna put the #1 car fourth on a 1m32.091s.
After sitting out the first half of the session, Ginetta's Team LNT showed some signs of life with WEC veteran Stephane Sarrazin putting the first laps on the board in the #6 G60-LT-P1.
Sarrazin completed seven installation laps, none quicker than the LMP2 runners, before posting the 10th-fastest time overall in the closing stages, a 1m34.670s.
The #5 Ginetta remained in the garage all morning after a delayed build-up.
United Autosports topped LMP2 with its brand-new ORECA 07, with Paul di Resta leaving it until the final 10 minutes to set the fastest time in class, a 1m33.344s.
That was enough to beat the second-placed Signatech Alpine ORECA of Andre Negrao by 0.308s.
Racing Team Nederland, now also running ORCEA machinery, was third-fastest in the hands of Giedo van der Garde on a 1m34.176s, narrowly ahead of the Cool Racing ORECA of Nicolas Lapierre.
Ferrari set the pace in GTE Pro, as Alessandro Pier Guidi and Davide Rigon set the quickest times in the #51 and #71 488 GTEs respectively in the third hour. Pier Guidi's 1m44.040s was sixth tenths quicker than the time Rigon set in the #71.
The brand-new Porsche 911 RSR-19s were third- and fourth-fastest, Gianmaria Bruni setting the German marque's best time of 1m44.922s, ahead of the sole Pro class Aston Martin Vantage GTE.
In GTE Am, Matteo Cairoli set the fastest time of the morning.
The test was red-flagged with an hour and 20 minutes remaining after an off at Turn 9 for David Heinemeier Hansson in the #57 Porsche, causing an 11-minute delay.