The Japanese driver has had to play second fiddle to BAR team-mate Button recently but claimed his share of the limelight with a lap of one minute 14.836 seconds in the final practice session before qualifying.

Sato's effort was almost three seconds faster than last year's pole position time at the Circuit de Catalunya, although slight changes to the lay-out contributed to that. Sato became the first man this weekend to break the 1min 15secs barrier, earning him top spot just 0.189secs clear of Ferrari's Michael Schumacher with Juan Pablo Montoya third for Williams.

Button was down in sixth, three-quarters of a second slower than team-mate Sato, with Renault's Jarno Trulli and Ferrari's Rubens Barrichello fourth and fifth respectively.

David Coulthard enjoyed an improvement after a trying time on Friday, taking seventh spot, outperforming McLaren team-mate Kimi Raikkonen and coming within a second of the fastest time.

Coulthard's early attempts to iron out handling difficulties on his McLaren were not helped by the Scot running wide with less than 10 minutes of the session gone.

But he hit form midway through the 45-minute practice to post the second-fastest time before being bumped down the standings late in the session.

Raikkonen enjoyed better fortunes after his car failure on Friday and held top spot for much of the session thanks to his first fast lap.

He was knocked down from first place by Mark Webber's Jaguar though, before the lap times really began to tumble as the last 10 minutes approached and he ended up 11th.