Jerez Test - Team Reports: Toro Rosso, Caterham and Marussia

Toro Rosso: A switch to Renault power would appear to have been a good move given their sister teams' success further up the field. However, given the problems that they and their counterparts have been facing this week, it may prove to be rather unfortunate timing.

Jean-Eric Vergne was first to drive the new STR9 on Tuesday morning, completing the third-highest number of laps of the day, behind Ferrari and Mercedes. Day 2 was to be far less promising for the team, however. Rookie Daniil Kvyat was scheduled to drive but reportedly due to problems with the Renault power unit, the Russian failed to complete a single lap.

JEV was back in the car for Day 3 and although he completed some laps, his new car stopped twice, due to mechanical issues. Kvyat ran on Day 4, completing 9 laps but again suffering a technical issue forcing him to stop on track.

These on-track problems have not allowed us to gauge a serious understanding of the Italian Red Bull teams' pace and it appears that they have some serious redesigning to do before the next test in Bahrain if they want to rack up some decent mileage before Australia.

Caterham: The Malaysian-backed Caterham squad got off to a shaky start after having to delay their planned 8am launch on Tuesday due to an undisclosed issue, this meant that the Swedish rookie Marcus Ericsson only had time for an installation lap.

He fared slightly better on Day 2, completing 11 laps and being the leading Renault powered car. Day 3 saw new reserve driver Robin Frijns not run at all due to a suspected technical issue, which was thankfully resolved overnight in time for the final day of testing.

The arrival of Day 4 saw yet another driver change, with the returning Japanse Kamui Kobayashi taking the helm. He completed a race simulation of 54 laps, allowing the team to gain some crucial data and telemetry of the CT05.

Caterham completed the most laps of any Renault-powered team throughout the week, not something that many people saw coming!

Marussia: Following the announcement of the team delaying the launch of the MR03 due to a technical issue that was to be resolved at the factory, Marussia's attendance at the Jerez test appeared to seriously be in doubt.

However, the issue appeared to be far less serious than first expected and the car was transported out in time for the afternoon of the third day on Thursday. Max Chilton was the first to drive the rather simple but effective looking car in the afternoon, completing an installation lap before the session ended.

Jules Bianchi took over running for their second day of testing, completing 25 laps, more than Red Bull had throughout the course of the entire week. The initial pace of the MR03 looks to be rather promising with Bianchi finishing 6th on the timesheets once the test had come to a close.

Providing that the Russian-squad's reliability can improve, they may be able to jump ahead of Caterham this season.

Tom Brooks
F1 Editor