Perez, who is gearing up for his debut season in Formula One, topped the timesheets with a 1:21.761, the fastest lap time seen at the Spanish circuit in the opening three days of the final pre-season test.However, the Mexican driver's time was set on a single lap flying runs - and his day was also not without problems, although through no fault of his own.
Having set his blistering lap time while focused on qualifying style runs, Sauber switched Perez to a race simulation in the afternoon. However, it was cut short when his C30 stopped out on track.
Ferrari's Felipe Massa, who amassed a massive 132 laps as the Scuderia's 150° Italia, demonstrated once again both the pace and reliability of his 2011 challenger. The Brazilian finished the day 0.331s off the pace.
But, perhaps more importantly for Ferrari, he was ahead of Red Bull's Mark Webber by 0.374s in what was an interesting tussle between the two title hopefuls, who went head-to-head during the morning session in qualifying short distance runs.
Rubens Barrichello claimed fourth place for Williams, but once again the FW33 ran into problems, with Barrichello bringing out the red flags on two occasions.
Michael Schumacher was next in line as Mercedes GP continued to introduce various upgrades to their W02. While the German ran the new exhaust in the morning session, further upgrades were added to his car in the afternoon.
"We've had a very productive day and completed a reasonable amount of mileage. We were able to check and confirm a lot of
things on the set-up of the car with the new upgrade package, and my initial impressions are certainly positive," said the seven-time World Champion.
"We've worked hard on reliability at the previous tests and our priority now is to develop and fine-tune the car which we have done quite successfully today."
Renault's Nick Heidfeld was the last driver to get within two seconds of Perez's P1 time, although he only completed 32 laps as his team-mate Vitaly Petrov was in action during the morning session. Petrov finished eighth with the Renault duo separated by Team Lotus driver Heikki Kovalainen.
The Finn was another who just ran once session as his team-mate Jarno Trulli was in action first. However, the Italian had a miserable time of things as his T128 suffered a gearbox problem followed by a water leak.
Adrian Sutil was ninth for Force India, ahead of Jaime Alguersuari, Jerome D'Ambrosio and Trulli.
Times
01. Sergio Perez Sauber 1:21.761 95 laps
02. Felipe Massa Ferrari 1:22.092 + 0.331 132 laps
03. Mark Webber Red Bull 1:22.466 + 0.705 97 laps
04. Rubens Barrichello Williams 1:22.637 + 0.876 105 laps
05. Michael Schumacher Mercedes 1:22.892 + 1.131 89 laps
06. Nick Heidfeld Renault 1:23.541 + 1.780 32 laps
07. Heikki Kovalainen Team Lotus 1:23.990 + 2.229 40 laps
08. Vitaly Petrov Renault 1:24.233 + 2.472 24 laps
09. Adrian Sutil Force India 1:24.334 + 2.573 108 laps
10. Jaime Alguersuari Toro Rosso 1:24.779 + 3.018 107 laps
11. Jerome D'Ambrosio Virgin 1:27.336 + 5.575 96 laps
12. Jarno Trulli Team Lotus 1:34.485 + 12.724 6 laps
Source: Planet-F1
