Yusuke Hasegawa does not yet know why the Honda engine in Fernando Alonso's McLaren failed
Alonso made it through the first part of qualifying but did not set a time in Q2, later revealing that the engine broke down during his hot lap.
The power unit will be replaced for Sunday's race and the Spanish driver will once again be fighting at the wrong end of the grid, hoping to achieve his first finish of the season.
But Honda head of F1 project Yusuke Hasegawa did not give McLaren much hope of progress after early investigations into the engine problems.
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"We are not sure the exact cause, but definitely a mechanical failure of the MGU-H [which works as part of the hybrid system] – something around the bearings was sticking and it happened three times here," Hasegawa said.
"It was very unfortunate.
"We are not sure why it has happened just here three times.
"But we suspect something has happened in this circuit or environment or characteristics.
"Possibly because the temperature is very high and the conditions are very sandy, but we don't know the cause."
Alonso, who was this week given permission to miss the Monaco Grand Prix and attempt to win Indy 500 instead, was particularly frustrated as he felt there was a chance of a top-10 spot on the grid.
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Fernando Alonso was seen in heated conversation with Yusuke Hasegawa at the Bahrain Grand Prix
"It's a shame. The lap was going well," Alonso said.
"I had improved half a second over the Q1 lap so I think we could have been 13th, 14th, 12th, depending on the others.
"But going into the final corner the engine broke down and I joined the pit-lane slowly.
"It was already [going to be] a hard race, but this makes it even harder.
"We have to change the power unit and without the chance to calibrate the engine a bit we will probably not run the race with all the power available, which is already little."