McLaren executive director Zak Brown has revealed that doubts about their relationship with Honda began as early as pre-season in Barcelona.
After the conclusion of FP1 on Friday in Singapore, a whole host of engine announcements were made with McLaren confirming that they will finally divorce Honda at the end of the season after a tricky three-year relationship together.
McLaren issued Honda with an ultimatum at the Canadian Grand Prix back in June, but Brown has said the beginning of the end really started after numerous breakdowns at pre-season testing in Barcelona, leaving McLaren on the back foot ever since.
"I don't think there was a specific tipping point, other than we knew we were in trouble in pre-season testing," said Brown.
"We needed to improve upon our 2016 results, so we knew we were in trouble then. We've spent quite a bit of time, most of it in the public domain, trying to find ways to get Honda competitive with us.
"We ultimately couldn't get there in the end, but it's great that they're staying in the sport."