While much of the media spotlight has fallen on world champions Mercedes, pace-setters Ferrari and 'newly married' Red Bull, Alfa Romeo - Sauber as was - has been quietly getting on with things, as drivers Kimi Raikkonen and Antonio Giovinazzi aim to help the Swiss-Italian team build on the progress made last season.

This morning, another piece of the jigsaw fell into place when Raikkonen posted the fastest time, albeit on the softest C5 rubber.

The Finn was 0.588s quicker than his former Ferrari teammate, Sebastian Vettel, who posted his best time on the C3 rubber.

Cloudier than the previous two days, the early part of the morning was dominated by the cars sporting the 'garden gate' aero rakes that look horrendous but are the necessary tools of the aero boffins.

With gates in place and the flo-vis generously applied, the drivers got to work, trying out the various compounds on offer, and some even running the unmarked Pirellis that are said to be closer to the C3 more than any other compound.

The only red flag of the session came when Pietro Fittipaldi stopped on track, necessitating the deployment of the flat-bed truck, but shortly after the Brazilian was back on track again.

Ahead of the session, Renault revealed that, following yesterday's failure, Nico Hulkenberg would not be running DRS, and would concentrate on short runs with the softer compounds.

As the drivers continued to try the various compounds, it was noticeable that Vettel's times on the C2s were more consistent than before, hinting that on previous days the Ferrari pair may have been deliberately over-pushing their tyres.

Round about the time Carlos Sainz made his first appearance of the day, behind the obligatory screens the Mercedes power unit in the back of the Williams roared to life, the FW42 having arrive at around 4 am.

Other than a late spin for Sainz, it was a largely uneventful morning, with each team carrying out its own programme, though Red Bull and McLaren, in particular, have far less laps under their belts heading into the lunch break than they will have wished.

The Ferrari continues to show pace and reliability, but in terms of laps completed, Mercedes leads the way this morning, with Valtteri Bottas having done an impressive 88 as the W10 continues to run like clockwork.

If Monday and Tuesday were FP1, today and tomorrow will be FP2, setting us up nicely for next week's FP3 and Qualifying.

No major surprises, other than the lack of mileage from McLaren and Red Bull, and the impressive pace of young Fittipaldi.

Providing Williams does get going this afternoon, George Russell will be on duty, while Lewis Hamilton takes over the Mercedes, Romain Grosjean the Haas and Daniel Ricciardo the Renault.

Check out our Wednesday gallery from Barcelona, here.