Jenson Button admitted that pole position for this weekend's Spanish Grand Prix - his third of the 2009 season - was 'unexpected' and his 'most satisfying' of the year to-date...but he warned of the necessity of a good start with the first KERS-equipped car right behind him on the second row of the grid.

Having secured the top spot in qualifying in both Australia and Malaysia, Button could do no better than fifth and fourth respectively in China and Bahrain, but the current Formula 1 World Championship leader proved that he is back on-form with a vengeance in Barcelona, in surmounting both handling woes throughout practice and a stern challenge from Brawn GP team-mate Rubens Barrichello to soar to P1 on his final lap - but he very nearly wound up starting right down towards the wrong end of the top ten...

"An unexpected but very pleasing pole position today, and it is probably my most satisfying pole of the season," reflected the 29-year-old, after having given best to Barrichello by more than two tenths of a second in the low-fuel Q2 session, invariably the first true indicator of 'real' pace over the course of the meeting. "Rubens has been really quick all weekend, and I was able to benefit from that by looking at his set-up to overcome some of the issues that we faced in practice yesterday.

"My final lap in Q3 was by far the best lap that I've had this weekend, but it was a bit close crossing the line with just two seconds to spare! The upgrades that we have on the car here are performing well, and it is certainly a good step forward for us although we haven't got the most out of the package yet.

"The team has done a great job with the developments, and I hope that everyone at the factory in Brackley and at Mercedes-Benz High Performance Engines in Brixworth enjoyed the pole today. It's really important to start from the front here as overtaking can be difficult, but we do have Felipe [Massa] behind us with KERS (Kinetic Energy Recovery Systems), so a good start will be crucial tomorrow."

If there had been question marks in the build-up to the first race of the European leg of the campaign about whether Brawn GP could successfully stave off the onslaught of the top flight's traditional 'grandees' like Ferrari, McLaren-Mercedes, BMW-Sauber and Renault, then qualifying at least seemed to deliver a firm answer - the big guns may be able to make improvements, but F1's newest giant-killing underdogs have been far from standing still either.

"Congratulations to Jenson for his third pole position of the season," remarked a delighted team principal Ross Brawn. "After some hard work from the team overnight, we were able to resolve the issues which Jenson encountered with our upgrade package yesterday and were greatly helped in that process by the input from Rubens. The developments on the car have enabled us to make good progress over the weekend, and whilst we are still to fully maximise their impact on performance, the signs are encouraging."