The former world champion ended up in a tyre wall after just 15 laps of his first day of testing in Spain.
Lewis Hamilton's testing debut for Mercedes ends in crash at Jerez
Lewis Hamilton's start to life with Mercedes-GP began in less than ideal circumstances today as he crashed 15 laps into his first day of testing.
The Briton, who was second quickest at the time, slid off into the tyre wall at the hairpin in Jerez.
Mercedes, on their Twitter account, said: "Lewis suffered a loss of rear brake pressure, the front brakes enabled him to slow the car but he couldn't avoid the barrier."
The team added the car had suffered 'obvious damange to the front wing and note'.
The 28-year-old locked up at 170mph on 'Dry Sack', the turn-six hairpin, before running off through a large stretch of gravel to hit the tyre wall with his front wing.
It had been the first time that the 2008 world champion had gone on track in public in a car that was not a McLaren-Mercedes.
Hamilton had been with the McLaren team since making his debut in the series in 2007, but signed for Mercedes last year on a three-year deal in October last year.
He and the team will be hoping for a more constructive today than yesterday when teammate Nico Rosberg was in the car, as an electrical fault ended the day's action after only 14 laps.
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