Carlos Sainz has topped day 2 of Bahrain pre-season testing for the second year in a row, doing so today with a lap time of 1:29.384 in his Williams. This is already a time quicker than that of Williams’ best qualifying lap in Bahrain last year. The two Ferraris made up the top three, with Lewis Hamilton just 0.052s ahead of Charles Leclerc.

Similarly to day 1, today’s running was intermittently affected by rain which somewhat set the track conditions back after having ramped up over the morning session. Though this slowed the running, it did mean we saw our first intermediate tyre running of the year and around Bahrain since 2017!

So what did we learn from day 2?

Mercedes lead the way for laps

George Russell and Kimi Antonelli put in some mighty shifts in the W16 today – with Russell completing 71 laps and Antonelli completing 87, totalling 158 for the German manufacturer.

Carlos Sainz set the most individual laps, putting in the equivalent of over 2.2 Grand Prix distances by completing 127 laps in his Williams FW47 – an impressive effort from the Spaniard.

The C4 makes its debut

The C4 tyre, one of the medium compounds available to the teams, made its first appearance of the year for just 30 laps total. Eight teams have opted for the C4 tyre as part of their selection, with Alpine and Aston Martin giving it a miss. Only Sauber, Williams, Ferrari and Racing Bulls ran the tyre today. Though it’s a medium compound, the C4 sits closer to the soft side of Pirelli’s six-strong compound range, and a special focus has been put on reducing the possibility of graining and degradation for this year’s version. As such, it’s likely to feature in several race selections over the year and so it’s valuable for the teams to experience with their new cars.

Haas’ gamble pays off

Haas were one of just two teams who added intermediate or wet tyres to their selection for the three days, and today it paid off. Rain fell on and off all day but Esteban Ocon took advantage of this and put his intermediate tyres to work with a few laps.

This was the first time the intermediate tyre had been used at the Bahrain International Circuit since in-season testing in 2017, where Daniel Ricciardo ran it on his Red Bull.

Red Bull making sense of their ‘new’ car…

Red Bull’s RB21 is remarkably similar to its predecessor, but Liam Lawson’s running was limited today by an apparent water pressure issue, perhaps giving us insight into what’s changed under the Red Bull’s bodywork.

Reports suggest that Red Bull have left their multi-stage cooling system in the past, instead opting for a less extreme solution that will offer improved weight distribution and better performance during race runs. It’s understood that this cooling system is more similar to that used in the dominant RB19, so could this be a case of taking one step back to take two steps forward for Red Bull?

Mercedes ‘fake’ duct?

Could Mercedes be running a ‘fake’ duct on the nose of their W16? The German manufacturer have had a hump on the nose of their car around the inboard suspension mounting points since last year, which nobody really knows the true function of. Mercedes now seem to have blanked off the front of this hump with a black panel, potentially designed to look as though the panel is open and acting as a driver cooling duct.

The image above shows the ‘duct’ in question, the black area is not an opening and instead is a black panel, creating confusion and raising questions around its true purpose.

Day three of pre-season testing gets underway on Friday morning at 10:00am local time (7:00am GMT) and will run for the usual morning and afternoon sessions of four hours each, with a one hour break between.

The drivers for these sessions can be found here.