McLaren has made 'no progress' in 2018 F1 season - Vandoorne

Alonso has previously pointed out that McLaren has suffered from not bringing major updates this season, apart from in Spain.

McLaren has had trouble identifying aerodynamic stalls on its car in the windtunnel, which has stopped it fixing its problems.

The team's sporting director Gil de Ferran said the race, which Alonso was eliminated from after being sent airborne in a spectacular first-corner crash, was "a disappointing end to a difficult weekend".

After qualifying, de Ferran had pointed out that although McLaren has primarily struggled with the aerodynamic performance of its MCL33 this year, Spa also exposed a major top speed deficit that has been another factor in its struggles.

McLaren was 2.3 seconds off the pace in Q1, almost a second more than its deficit in the same session last year.

It is understood to be suffering from misjudged gear ratios, set at the start of the year, that at Spa left the cars bouncing off the rev limiter too early.

"There's no shying away that it's been a difficult year so far," said de Ferran.

"This is a difficult car. Particularly this weekend has exposed a lot of our weaknesses, mainly in straightline speed.

"The car has other issues as well, but that's a big one which became very apparent here."

Vandoorne said McLaren cannot hide from its bad performance in Belgium, which he admitted did not come as a surprise.

He thinks McLaren will probably need to wait beyond this weekend's Monza race for a better showing based on its showing at Spa.

"There haven't been many encouraging things this weekend," he said. "It wasn't the nicest race of the year.

"Monza will be very difficult again. It's again a circuit with a lot of straights

"We'll see. Maybe we have a couple of opportunities later in the year to score some points, like in Singapore."