Mercedes ended the first pre-season test on top as Valtteri Bottas led teammate Lewis Hamilton on Day 3 in Barcelona.

Having focused on race simulations on Thursday, the Brackley-based team loosened the reins a little on the W11, as both drivers conducted fast laps on the C5 Pirelli tyre.

And it was Bottas who had the better run, posting a 1m15.732s in the morning to go just three-tenths slower than the overall lap record around the Circuit de Barcelona-Catalunya, that being the pole position time the Finn set for last year's Spanish Grand Prix.

Hamilton's attempt on Pirelli's fastest compound was much less tidy as a bad final sector saw him finish eight-tenths behind Valtteri, but it was still enough to claim second place on the day.

After just one red flag across the first two days, the third would see four, two in the morning and two in the afternoon.

The first was caused by Sebastian Vettel's Ferrari, which came to a halt in the final sector with an engine issue just 90 minutes in.

A quick change saw the German back on track after lunch, however, he would end the day only 13th fastest as team boss Mattia Binotto accepts the SF1000 is behind their fellow top three rivals.

Another stoppage came after Nicholas Latifi lost drive on the main straight. A quick reset seemed to have fixed the issue, but Williams later opted to change the Mercedes engine in the FW43 before returning to the track for the final hour of running.

As a result, the Canadian only managed 73 laps and was 15th fastest.

Early in the afternoon, Kevin Magnussen caused the third suspension of the day after spinning into the gravel on the exit of Turns 7 & 8 after just four laps.

A right-rear puncture was quickly seen as the cause but it was a big setback for Haas, who only managed 52 laps in total after Romain Grosjean drove in the morning.

The final red flag belonged to Daniel Ricciardo, who stopped with an engine problem of his own in the Renault before later rejoining.

Before that, the Australian had been on a good race simulation, matching the pace seen by Mercedes and Red Bull.

And it was still a productive day for the French manufacturer, who had Esteban Ocon in third and managed an impressive 169 laps across the two drivers.

Racing Point ended the week as one of the standout performers as Lance Stroll finished fourth with a very solid 116 laps on the board.

AlphaTauri went more under the radar but also impressed again with Daniil Kvyat fifth and Pierre Gasly ninth.

Antonio Giovinazzi was sixth and ended as the marathon man on Friday with 152 laps to his name, the most for a single driver.

His time also meant just under four-tenths covered P3-P6 with all four using the C3 tyre, offering a hint at how competitive this year's midfield will be.

Red Bull had another productive day with Max Verstappen eighth and Alex Albon 10th, the two drivers combining to match Renault's figure of 169 laps on the day.

The final team to mention is McLaren, where Carlos Sainz was 11th with teammate Lando Norris 14th. This as the British team's subdued start to testing continued.

Full results and lap counts from the final day of the first winter test can be seen below: