Ferrari driver Sebastian Vettel got off to a good start as the final week of Formula One testing began on Tuesday, setting the fastest time and running the most laps at the Circuit de Catalunya-Barcelona on Tuesday.
Vettel showed Ferrari's strength by finishing the day with a time of 1 minute, 20.396 seconds, two tenths faster than Valtteri Bottas of Mercedes. Max Verstappen was close behind with Red Bull, followed by the Mercedes of defending champion Lewis Hamilton.
Vettel ran 171 laps on Tuesday, 41 more than Verstappen, the driver closest to him on the lap charts. The only other driver to break the 100-lap mark was Marcus Ericsson of Sauber, with 120. Mercedes totaled 177 laps as Hamilton and Bottas split driving time.
Red Bull driver Max Verstappen of the Netherlands steers his car during a Formula One pre-season testing session in Montmelo, outside Barcelona, Spain, Tuesday, March 6, 2018. (AP Photo/Manu Fernandez)
McLaren, using a Renault engine this season after three dismal years with Honda, struggled with reliability issues as Stoffel Vandoorne was twice stranded on the track. The team said "a power shutdown" caused the problem.
Vandoorne ended the day with 38 laps, the fewest among the 13 drivers who were on the track. The Belgian driver had the third-fastest time overall in last week's tests.
Vandoorne's teammate, two-time world champion Fernando Alonso, ran a few laps on Monday on a "filming day," but he will not test until Wednesday. Practice is restricted in F1 but teams are allowed to take their cars to the track for a few brief periods for marketing and commercial purposes.
Sauber driver Marcus Ericsson of Sweden steers his car during a Formula One pre-season testing session in Montmelo, outside Barcelona, Spain, Tuesday, March 6, 2018. (AP Photo/Manu Fernandez)
Sergio Perez caused a red flag after spinning in the morning session, and Verstappen stopped on the track in the afternoon.
The first four days of testing were hampered by bad weather and cold temperatures in Barcelona, keeping teams from making quality runs on a track that lacked enough grip and didn't reproduce the conditions expected during the season.
Hamilton was fastest last week with a time of 1:19.333.
Ferrari driver Sebastian Vettel of Germany steers his car during a Formula One pre-season testing session in Montmelo, outside Barcelona, Spain, Tuesday, March 6, 2018. (AP Photo/Manu Fernandez)
Teams will test until Friday.
The season begins with the Australian Grand Prix in Melbourne on March 25.
Sauber said Tuesday it signed Tatiana Calderon as its test driver for 2018. The 24-year-old Colombian driver was the team's development driver last season.
Mercedes driver Lewis Hamilton of Britain walks in the paddock during a Formula One pre-season testing session in Montmelo, outside Barcelona, Spain, Tuesday, March 6, 2018. (AP Photo/Manu Fernandez)