McLaren says that it identified a crack in Daniel Ricciardo's chassis that may have caused the Aussie's sudden power loss and subsequent retirement from the Sao Paulo Grand Prix.
From eleventh on the grid, Ricciardo gained a position at the start of Sunday's event and was racing comfortably among the top ten when his race was undermined after 50 laps by a power loss.
A reliability issue came to mind in the McLaren camp given the multiple power unit changes undertaken recently by Mercedes and its engine customers.
But a more in-depth investigation by McLaren revealed another potential cause for the sudden power los.
"We had a power loss on track, and in the initial investigation we found a technical issue, a crack on the chassis side of the power unit installation, which we now need to investigate," explained team boss Andreas Seidl.
©McLaren
Ricciardo was understandably frustrated by the issue as he had put his head down in the race and was hopeful of "hanging on" to Ferrari's chargers with a McLaren car that was performing better than in Saturday's sprint race.
"It was definitely better than yesterday, I say better than yesterday but I think it was actually going well," Ricciardo commented.
"We were in the fight, or at least hanging on to the Ferraris [who] we knew had to two-stop, because they went medium-medium, so we were potentially going to try to do a one [stop], or we had the ability to being on the hard.
"And Gasly was there in our window as well so I think it could have got interesting. But anyway we were doing what we could, and we just had a loss of power at the end so we had to retire the car.
"But had some battles, I think it was a much more interesting race than yesterday and we were at least in the mix, in the fight.
"I think we still lacked maybe a couple of tenths, but I think we were there, so come back in Qatar. I heard it is my first retirement all season, so these things happen."
Unfortunately, Ferrari's double top-ten finish in Brazil has allowed the Italian outfit to further increase it lead over McLaren in the Constructors' standings, with the Scuderia sitting third, 31.5 points ahead of its rival in fourth place.
Gallery: The beautiful wives and girlfriends of F1 drivers
Keep up to date with all the F1 news via Facebook and Twitter
