Piastri appeared to lock up when hitting the exit kerb of turn four, skidded and slammed into a barrier, damaging his right front wheel, the front wing and nose of the car.
Piastri, third in the championship last season, said he was OK on the team radio and exited the car before walking back to the pit.
McLaren boss Zak Brown said they were now focusing on the one car they had in the race driven by defending champion Lando Norris.
"We've not seen anything on the data so far," said Brown.
"He didn't say anything on the radio. So we'll do a post mortem after the race and see what happened.
"For now, we've got to focus on the car we have in the race and get the excitement level back up."
Piastri was to have lined up fifth on the grid.
F1's new engine era has proved a steep learning curve for drivers, with a number struggling with reliability problems and the new way of driving which involves more emphasis on energy deployment and regeneration.