Sergio Pérez topped the timesheets on the penultimate day of testing in Barcelona that was interrupted by rain towards the end of the session. The Sauber driver set a lap time of 1 minute 22.094 on Pirelli’s soft tyre compound – three tenths slower than the time that put him quickest on Day 3 of last year’s test at the Circuit de Catalunya.

A whole new driver line-up awaits the STR7, the third car designed by Toro Rosso themselves. A strong finish to their 2011 campaign gives the outfit hope of a good start but much will depend on how Daniel Ricciardo and Jean-Eric Vergne bed in at Red Bull’s sister team.

I’ve taken a look at the qualifying performance of three of the teams occupying mid-field positions, Williams, Toro Rosso and Force India. Has their development rate kept pace with the front runners as Team Lotus seems to have done, or are they falling further behind?

In India the drivers were asked to sign some children’s artwork, and so for this week’s Caption This… we plumped for the Toro Rosso pairing of Sebastian Buemi and Jaime Alguersuari, mostly because recent performances suddenly reminded us that they actually exist. Sorry boys – blame your big brother over at Red Bull. Anyway, we’re looking for captions for this picture, so ladies and gentlemen, do your best worst…

This week’s Caption This… takes us into the Toro Rosso garage where the team seem captivated by something. What exactly is up to you as you get to provide a caption for the picture. What are they thinking/saying? It’s over to you…

With the last opportunity for the teams to put their machinery to the test on the track ahead of the opening race now gone, we take a look at how the teams have faired. We analyse their prospects for the new season and highlight some potential weaknesses…