Sochi - A crestfallen Lewis Hamilton vowed on Saturday to "never give up" in his world title defence after another engine failure wrecked his hopes in qualifying for Sunday's Russian Grand Prix.
The defending three-time world champion was unable to take part in the Q3 top-ten shootout as his Mercedes team-mate Nico Rosberg cruised to a 24th career pole position by seven-tenths of a second.
He also suffered an engine failure at the Chinese Grand Prix where he started from the back of the grid and has been involved in opening lap accidents in all three races this year.
In Shanghai, he recovered from last to finish seventh. This time, he said, he only wanted "just to recover from wherever I start tomorrow(Sunday). There's nothing I can do.
"But, you know, I never give up."
Rosberg, seeking his first world title, has taken full advantage and won all three races this season to open up a 36-point lead ahead of Hamilton in the championship.
This time, Hamilton suffered his power unit failure on his outlap for a second run during Q2, after topping the times in Q1.
As a result, he qualified 10th, but may face a further setback if he is given a grid penalty for a change of engine ahead of Sunday's race.
Hamilton said the power unit problem was similar to that which he suffered in China.
"This was the second engine (of the season), from the last race. And the same failure I had in the last race as well. I went back out in Q2 at the end to get a feel of it and I lost the same power as I lost in China."
His Mercedes team boss Toto Wolff admitted: "It's a very bizarre situation. It seems like the same failure as in Shanghai, which means we have to reassess the root cause of the problem.
"But this is motor racing and it can happen. Lewis seems to have all the bad luck and the other side of the garage has all the luck.
"I hope there is no penalty for Lewis, but we need to discuss that with the FIA (International Motoring Federation) to see what we want to do and make it without a penalty.
"It's getting tough for Lewis now and I have no doubt he will come out of it. But, right now, he has every right to be upset."