Rubens Barrichello has ended the Jerez test on the top of the time sheets in his Williams.

The veteran Brazilian clocked a 1:19.832s lap on the fourth and final day to emerge quickest, as the fancied teams continued to put in quiet performances.

Barrichello completed more than 200 laps of running over the final two days, after team-mate Pastor Maldonado had been restricted to just 52 thanks to mechanical issues on Thursday and Friday.

For the second time in three days, Sauber emerged second fastest, with Kamui Koboyashi 0.8s slower than Barrichello.

The Williams and the Sauber caused one red flag each however, with Barrichello stopping with a hydraulic leak, and Kobayashi making a visit to the gravel trap.

Fernando Alonso was third fastest in the Ferrari, having concentrated on long runs in the afternoon.

Sebastien Buemi was fourth, having spent the late afternoon sampling the Pirelli intermediates as bad weather moved in.

Bruno Senna had his first run in the Renault R31 and was fifth. Having had just one test day with HRT in 2010, the Brazilian reported the usefulness of spending a full day behind the wheel, but is not in contention for the race drive vacated by the injured Robert Kubica.

Heikki Kovalinen was an encouraging sixth fastest for Lotus, despite running just 43 laps due to a water leak.

Nico Rosberg again suffered at the hands of the Mercedes W02’s unreliability. The German was seventh fastest, after the team completed an engine change following just 18 laps of running in the morning.

Sebastian Vettel and Jenson Button were eighth and ninth fastest, with Red Bull concentrating on long runs and McLaren left to lament reliability issues.

Rookies Jerome D’Ambrosio (Virgin Racing) and Paul di Resta (Force India) rounded out the field.

Testing recommences on Friday in Barcelona.

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