The Sauber F1 Team brought some aerodynamic updates to the Spanish Grand Prix in Barcelona, which Nico Hulkenberg and Esteban Gutierrez tested mainly in the first free practice. In the afternoon the primary focus was on tyre comparisons combined with high fuel loads. The results were satisfactory in the morning, but looked less pleasing in the afternoon.

Nico Hulkenberg: The day was ok. Unfortunately we could not run our aero programme as planned due to the rain in the first session this morning, but you can't change the weather and the situation was the same for everyone. We were able to work through the whole programme during the second free practice without any problems. The new rear wing is an improvement. However, if it's enough of an improvement to catch up to our competition I can't say yet.

Esteban Gutierrez: We were able to work through the whole programme today. The stability of the car has improved, which gives me more confidence to push during the long runs. We were able to analyse the new parts we brought to Barcelona. The team is doing a good job and we are pushing to be able to close the gap to our competition. It's hard to judge where we stand at the moment, but I think qualifying tomorrow will show where we are at compared to the rest of the field.

Tom McCullough, Head of Track Engineering: Obviously a wet start to P1 is not ideal when you are trying to evaluate development parts and the different tyre specifications. But that's the same for everybody. We split the programme between the two cars to gather as much data as possible. It's clear we have some work to do, so we will analyse the data tonight and put together the best possible car for tomorrow.

Check out our Friday gallery, here.