The reigning world champions left the Canadian Grand Prix without a point after both Norris and Oscar Piastri started on intermediate tyres in drying conditions before the strategy quickly unravelled.
Norris briefly made the call look inspired when he launched from third on the grid to lead into Turn 1, but the improving conditions rapidly swung against McLaren after multiple extra formation laps delayed the start.
Piastri stopped for slick tyres at the end of the opening lap, with Norris following one lap later after initially staying out in the hope of a safety car.
The Briton’s race then became increasingly complicated after an unscheduled stop on Lap 15, before his afternoon finally ended on Lap 40 when he pulled over at the Montreal hairpin.
McLaren team principal Andrea Stella later confirmed Norris had suffered two separate reliability problems.
“With Lando, we had two issues,” Stella explained.
“One was that the car started to overheat, therefore we needed to stop relatively early, which was to clean the radiators, and I’m not sure how clear this was on television.
“But the stop was actually for reliability problems, and then there was a gearbox problem which was independent of this overheating.
“This gearbox problem would have happened in all cases, so it was not Lando’s day; he would not have finished the race.
“So if there is a day to have all the problems in a single [race], then this was that day.”
Piastri’s race also unravelled after the early tyre stop, with the Australian later colliding with Alex Albon while attempting a pass on the Williams driver.
The contact forced Albon into retirement, while Piastri received a 10-second penalty and eventually finished 11th.
Stella agreed with the stewards’ verdict for Piastri’s incident with Albon.
“It was a misjudgment,” he said.
‘Looked like idiots’: Piastri reacts to McLaren’s Canada disaster
“Obviously there must have been some pressure as well to try and recover, but ultimately this was penalised by the stewards and it was also penalised by the fact that the car was damaged.”
The McLaren boss added the damage left Piastri unable to recover ground later in the race.
“I’m not sure that was possible to catch up after the issues we had at the start. The car was damaged, so Oscar lost some performance because of aerodynamic reasons.”
Despite the earlier tyre strategy backfiring, McLaren strongly defended the decision to begin the race on intermediates.
Stella believed the unusual double-aborted start procedure, caused by Arvid Lindblad stalling on the grid and marshals failing to remove his Racing Bulls car in time for the restart, ultimately swung conditions away from McLaren’s favour.
“I think it’s a bit unlucky with the fact that the rain just stopped, and the fact that there was a double extra formation lap which I’m not sure exactly when is the last time that we saw it,” he said.
“So, in hindsight, we were penalised by the decision. But at the time that the decision needed to be made. I think the conditions existed to fit an intermediate tyre.”
Both Norris and Piastri said worsening conditions before the start convinced the team the crossover point favoured the intermediates, only for the rain to ease during the delayed formation procedure.
Piastri admitted the outcome left the team looking foolish.
“It’s just one of those things where if it rained a little bit more we would have looked like heroes, but it didn’t, so we looked like idiots,” he said.
Norris also rejected suggestions the call had been reckless.
“I just had a lot more grip,” Norris said of his opening lap charge.
“It shows how slippery it was for them in the beginning, and I had a two-second gap after one lap.
“It wasn’t like it was stupid to be on that tyre.
“1% more rain or a few little bits of drizzle here or there and it really would have suited us a lot more.”
The team will now switch focus to the Monaco Grand Prix, where it will celebrate its 1000th grand prix.
