Sebastian Vettel set the pace for Ferrari in a tightly-packed field as the second and final pre-season test began in Barcelona.
The German set a 1m20.396s on the Medium compound tyre towards the end of the morning, exactly two-tenths clear of Valtteri Bottas' Mercedes with the Finn managing his best on the Soft Pirellis.
Vettel also covered the most distance for an individual driver with a remarkable 171 laps of the Spanish Grand Prix venue, though most teams would manage extensive programs as they look to make up for the time lost last week.
It would be the world champions who did the most laps for a team, however, with Bottas and Lewis Hamilton combining for 177 tours.
Max Verstappen would be third in the lap times just over a quarter of a second off the leading pace and, despite causing the final red flag after stopping at Turn 1 it would only be a small problem with the Dutchman returning and tallying 130 laps for Red Bull.
Hamilton would be fourth in his Silver Arrows after running in the afternoon when times are often slightly slower, with Pierre Gasly fifth as Toro Rosso showed better pace but would have their first setback following brake problems.
Kevin Magnussen was a solid sixth for Haas ahead of the two Renault drivers as Nico Hulkenberg pipped Carlos Sainz by 0.023s but the Spaniard completed almost double the number of laps.
Williams had a steady day with Sergey Sirotkin a respectable ninth and Lance Stroll seemingly focused on long runs as he brought up the field despite being the only driver to use the Hypersoft tyre.
Both Sainz and Stroll were potentially set for the first full race simulations of pre-season but ill-timed red flags scuppered those plans.
Sergio Perez was 10th on another quiet day for Force India, though the Mexican did manage 93 laps after having the lowest total last week. He led Marcus Ericsson in the Sauber, though the Swede would travel further with 120 laps.
A big story from Tuesday was the woes at McLaren as Stoffel Vandoorne had three car shutdowns due to electrical issues as the British team also struggles for cooling with the new Renault engine.
Following his second on-track stoppage in the afternoon, the Belgian would not re-emerge ending with the lowest lap total of just 38. Hardly the ideal way to start what is meant to be a new chapter for McLaren.
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