On a weekend McLaren expected to significantly add to its points haul, thereby further consolidating its fourth position in the standings, the Woking outfit came away from Mexico empty handed.
Carlos Sainz lost ground once he switched to the hard tyres, while teammate Lando Norris' race was ruined by a botched pit stop which saw the Briton grind to a halt at the end of the pitlane as it appeared his wheel was loose.
""Stop the car, we're coming to get you," said Norris' engineer as the McLaren slid down the timesheets.
The Briton rejoined the race in last position, in a bid to "prove what might have been", but as he continued over a lap down on the rest of the field he was eventually told to retire the car.
Feeling that the Briton was released unsafely the stewards investigated, which is where it got confusing.
Reviewing video and audio evidence of the pit stop in addition to hearing from a McLaren representative and the FIA Technical Delegate, the stewards heard that the front left mechanic was not sure if the tyre was secured properly therefore they decided to stop the car for caution.
After reviewing the video evidence, the FIA technical delegate could not establish if the car was in an unsafe condition after being released, therefore the stewards considered that with the available evidence it was not possible to determine if the car was released in an unsafe condition or not, as a result no further action was taken.
"I think we had a wheel nut cross-threaded at my stop," said Norris, "I'm not too sure, but the team decided to play safe by immediately stopping the car and bring it back to check it.
"I was running pretty much a lap down and had several blue flags which made the race even more difficult. Some parameters of the car were beyond the limit and we retired to avoid further damage."
"We unfortunately had an issue with the wheel nut on one corner at Lando's pit-stop," added team boss, Andreas Seidl. "Our policy is to be completely safe and we stopped the car immediately to check it and fix it, even if this meant his race was over very early.
"Later, some of the parameters of his car were over the limit, so we decided to retire him to save further damage."
Check out our Sunday gallery from Mexico City, here.