McLaren pair Fernando Alonso and Jenson Button were left to rue problems which scuppered their prospects during qualifying for the Hungarian Grand Prix.
Alonso made it through to Q2 but his car slowed before he had set a lap and he stopped due to a loss of power.
The Spaniard attempted to push his car back to the pit lane but was unable to take any further part in the session.
"It was not too bad but I was not allowed to compete again in qualifying after the car doesn’t arrive by itself in the garage so when I knew the rules I thought 'why push so hard?'
"It’s unlucky, I think it’s something electrical or some connector as the power was off immediately."
Team-mate Button failed to progress from Q1 as he received no extra power as he drove down the pit straight.
"We didn’t get any electric power, all the way down the straight, about three tenths, would have been easily through to Q2," he said.
"I really enjoyed driving it today, this morning was a bit tough, oversteer on exit, but in qualifying it felt good, I know we’re not quick but the balance felt right, I think we would have been 12th or 13th but we just have to deal with it."