Alonso claims McLaren-Honda losing 2.5s per lap at Sochi F1 track

The Spanish driver finished qualifying for the Russian Grand Prix in 15th position with a lap 3.466s seconds slower than Sebastian Vettel's pole position time.

Alonso was heard saying "unbelievable" on the radio at the end of the second qualifying segment, in which he finished last.

"It's unbelievable how much we lose on the straights," said Alonso.

"I think it was 1.3s in the first sector and there's just one corner and we have no problems there, so that's what we have.

"On the straights we lose 2.5-three seconds on this circuit. We knew it already before getting here, but then qualifying arrives and you always want a bit more."

Alonso was still delighted with his own performance in the session despite lapping three-tenths slower in Q2 than he did in the first segment of qualifying.

He lapped seven-tenths faster than team-mate Stoffel Vandoorne, who qualified 17th, in Q1.

"I think it was a basically perfect qualifying," said Alonso.

"The Q1 lap would be hard to repeat. In Q2 I made a few mistakes, but Q1 was very good.

"Seven tenths to my teammate, with the same car, someone who has won in all categories before reaching Formula 1, so I still feel at the peak of my form and in my best moment."

Alonso, who has yet to take the chequered flag in 2017, added that he expects another difficult race in the vein of the first three of the season.

"Every Thursday, Friday, Saturday and Sunday I stand here before you and I try to answer in the most polite manner but it's going to be a bit monotonous, a bit of the same story like it's always been in Formula 1," said Alonso.

"We can already say that Ferrari and Mercedes will fight for victory this year, that Red Bull will try to be on the podium, that Williams will be in the points, and the rest we'll try to grab a point when the rest allow it.

"So we'll try to have a perfect race but be aware of our limitations."