Fernando Alonso believes his charge to seventh place in Formula 1 qualifying for the Spanish Grand Prix proves McLaren's belief that it has one of the most competitive chassis on the grid.

Following a torrid start to the season that has seen him fail to score a single point or see the chequered flag, Alonso stunned the F1 paddock by dragging his McLaren-Honda MCL32 to seventh place in Barcelona on Saturday.

Alonso's result was made all the more impressive by the fact that his top speed through the speed trap was the 19th-fastest of the session - only faster than that of team-mate Stoffel Vandoorne - and some 12 km/h down on leader Sebastian Vettel.

Speaking after the session, Alonso said the result acted as evidence of McLaren's long-held belief that it has one of the strongest chassis in F1, with the majority of the time lost being down to the power unit.

"It's still nearly two seconds from pole position so it's still a big gap," Alonso said. "But we know how much we are losing from the power unit.

"So I think from the chassis side we more or less confirmed what we thought at the beginning of the year and the first races - that we are quite competitive and we are happy with the things that are happening on the chassis side.

"It's still not the best, I still think there's some work to do aerodynamically and mechanically. I think we need to keep working to be at the level of Mercedes and Ferrari who definitely are a little bit ahead of everyone.

"But we could be right behind them in terms of chassis."

Alonso recognised that the less power-hungry nature of the Circuit de Barcelona-Catalunya played into his hands, allowing McLaren to fight higher up the order.

"I think we came from two difficult circuits. Bahrain and Russia the power sensitivity there is quite high so we struggled a little bit more," Alonso said.

"Here is I think the fourth or the fifth-lowest, so we benefit a bit for that. Monaco I guess will also be a good opportunity for the team, Hungary and Singapore, so the normal circuits with low power sensitivity.

"Today we executed the qualifying well, the car was performing well, the conditions were tricky - quite windy - but I felt good with the car, confident. The last couple of laps were good enough to be in Q3 and then good enough to be P7.

"It was close, 0.1s for three or four cars, so we knew that we needed to put a perfect lap together and today was one of those days when everything went our way and everything went fine."