* Hamilton on pole for eighth time in nine races
* Mercedes sweep front row
* Williams on second row, Ferrari pair behind (Adds detail, quotes)
By Alan Baldwin
SILVERSTONE, England, July 4 (Reuters) - Formula One champion Lewis Hamilton gave the British Grand Prix crowd what they wanted by powering to pole position in a one-two with Mercedes team mate and title rival Nico Rosberg on Saturday.
The pole was Hamilton's eighth in nine races and the 46th of his career for the championship leader, who took a home win at Silverstone last year and has a 10 point advantage over the German.
Brazilian Felipe Massa qualified a strong third for Williams, ahead of Finnish team mate Valtteri Bottas, with the Ferraris of Kimi Raikkonen and Sebastian Vettel lining up together on the third row.
Hamilton's first flying lap in the final phase of qualifying proved good enough for pole, with Rosberg complaining afterwards that there was a problem with the left front wheel of his car.
"It's a special day," said the Briton, now third on the all-time list of pole-setters behind Michael Schumacher and the late Ayrton Senna.
Champions Mercedes have now taken 20 poles in a row, four short of Williams' all-time record set in 1992-93.
"It's special when you get the pole position here on your home turf and you see all those fans out there, so many people have come today," added Hamilton, who has now been on pole three times in Britain.
"They really do motivate me," he said of a crowd that exceeded 100,000 on Saturday and is expected to reach a record 140,000 on Sunday.
The 30-year-old saved the best for last, struggling on Friday when Rosberg was fastest. He was only fourth fastest in the opening phase of qualifying and third in the second with the German again ahead of him in both.
"It's not been the smoothest of weekends, been a bit up and down in terms of setup and balance," said the champion.
"Once we got to Q3 (the final phase) I could just go all out and get that lap in."
Rosberg, winner of three of the last four races and on pole at Silverstone last year, was just 0.113 of a second slower than Hamilton's best time of one minute 32.248 seconds.
"The last run, nobody or not many improved," he said. "There was something wrong with my left front so I had big understeer -- something very wrong," he said.
Stewards warned drivers before qualifying that they would be keeping a close eye on those gaining an advantage by using the runoff and they deleted lap times set where the driver had exceeded the track limits.
Eleven of the 20 drivers fell foul of the stewards as a result, including Raikkonen and Vettel.
Honda-powered McLaren's miserable season continued with Spain's Fernando Alonso qualifying 17th and Jenson Button 18th in his home grand prix.
Despite that, Alonso said it was still the struggling team's "best qualifying of the year", given the gap to Ferrari of just 1.5 seconds on a fast and long track.