Thanks to fresher tires, Webber was able to catch up with pole-sitter Alonso, who led for most of the 52-lap event, pass him, and beat him to the finish line by 3.1 seconds.
Webber notched his second win of the season, the ninth of his Formula One career and his second British Grand Prix victory in three years.
Webber used the victory to reduce Alonso's lead in the world championship standings to 13 points.
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