Lewis Hamilton's first day of testing for Mercedes lasted just 15 laps before a rear brake failure on the W04 caused him to crash heavily into a tyre wall in Jerez.
The team are currently repairing the damage to the car with no word yet on when it will be ready.
Hamilton had just set the second-quickest time of the day before locking up the front tyres at Dry Sack hairpin - made famous by a clash involving Michael Schumacher and Jacques Villeneuve in the 1997 title decider.
Lewis Hamilton's Mercedes is lifted onto a truck after crashing into gravel at Circuito de Jerez in Jerez de la Frontera, Spain (PA)
The Briton, 28, travelled straight through the gravel trap and into the barriers.
Hamilton emerged unhurt and watched as the tow truck winched the car onto its transporter, safely covered in a blanket to hide its secrets.
Mercedes later tweeted: "Lewis suffered a loss of rear brake pressure, the front brakes enabled him to slow the car but he couldn't avoid the barrier... Obvious damage to the front wing and nose; we are checking the car over now... Lewis himself is fine..."
Lewis Hamilton during testing at Circuito de Jerez, Jerez, Spain (PA)
Hamilton's Mercedes team-mate, Nico Rosberg, managed just 14 laps on the first day of winter testing on Tuesday before an electrical fault ended his day, with flames briefly billowing out of the exhaust.
With track time at a premium - there are only three four-day tests before the first grand prix of the season in Melbourne on March 17 - Mercedes will be anxious to fix the car and get Hamilton back out on track as soon as possible.
Lewis Hamilton during testing at Circuito de Jerez, Jerez, Spain (PA)Hamilton's Mercedes team-mate, Nico Rosberg, managed just 14 laps on the first day of winter testing on Tuesday before an electrical fault ended his day, with flames briefly billowing out of the exhaust.
With track time at a premium - there are only three four-day tests before the first grand prix of the season in Melbourne on March 17 - Mercedes will be anxious to fix the car and get Hamilton back out on track as soon as possible.
