The Alpine Formula 1 team will investigate the root cause of the failures which eliminated Fernando Alonso and Esteban Ocon from the Singapore Grand Prix.

Both drivers were forced out of the event with power unit failures, Alonso rolling to an inconspicuous halt while Ocon’s let go in a spectacular plume of smoke.

Rubbing salt into the wound was a double points finish for McLaren, which has now overhauled Alpine for fourth in the constructors’ championship – a 22-point swing in that battle.

“Unfortunately we had a double retirement from today’s Singapore Grand Prix, which is a pity as we’ve been very competitive all weekend,” said team boss Otmar Szafnauer.

“It looks like we suffered a similar power unit issue on both cars, which we will investigate in detail.

“It’s important that we identify the root cause of what happened and put preventative measures in place to avoid a repeat.

“In terms of the progress of our race, it was challenging with the drying conditions and we were about to enter a window where could have made the call for dry tyres before our retirements.

“These days do happen in racing from time to time and while it’s a disappointing feeling within the team now, we have another race next weekend in Japan where we have the opportunity to recover.

“As a team, we’ll take this one in our stride and we already look forward to returning to Suzuka and racing at a fantastic circuit.”

Alonso was running sixth when he was forced out, fending off the recovering Max Verstappen as the Dutchman worked his way through the field after a poor start.

The Spaniard’s race ended on Lap 21, pulling off the road at the Singapore Sling.

It’s a retirement that will have a knock-on for the two-time world champion who now faces the prospect of a grid penalty at a future event.

“I think the engine mileage is okay. Esteban had the problem today and he has a newer engine, so I don’t think this is down to that,” he reasoned.

“I will have to put a new engine in at the next few races and we will see when. More points that we will lose.”

Alonso restated his belief that reliability issues this year have cost the team dearly, especially given it has now slipped a place in the teams’ championship.

“If you put me 60 points more in the standings and you reduce obviously 10 or something from the others, because you take points from the others as well, my championship would look much better and close even to the Mercedes,” he suggested.

“That probably is more accurate of the performance that we have put in this year of which I am very proud, even today. Another top five, top six we were fighting for.

“But the standings don’t translate the true performance.”

Ocon’s race lasted only until Lap 27 when his Renault power plant cried enough, coming at a similar place on the track to Alonso’s.

The Frenchman’s car bellowed smoke as he crossed the Esplanade Bridge, coming to a halt just three corners further up the road to his team-mate.

McLaren now leads Alpine by four points in the constructors’ championship with six races remaining, the next of those in Japan this weekend.