McLaren have heaped further pressure on Honda by describing Fernando Alonso's retirement from the Canadian Grand Prix as "absolutely not good enough".
Alonso was only two laps away from scoring both his and McLaren's first point of the campaign, only for his Honda engine to expire.
The 35-year-old Spaniard has retired from five of the six grands prix he has competed in this season, while teammate Stoffel Vandoorne is also yet to finish inside the top 10. McLaren are the only team yet to score a point this year.
The British team's executive director Zak Brown upped the ante on Honda earlier in the week by labelling the beleaguered Japanese manufacturer as "lost" before Eric Boullier, the team's racing director, added further fuel to the fire in Montreal.
"For the first time this season, running in 10th place within spitting distance of the flag, we dared to hope," Boullier said.
"OK, what we were daring to hope for were hardly rich pickings: a solitary world championship point for Fernando, who had driven superbly all afternoon, as he's driven superbly every race-day afternoon for the past two-and-a-half years.
"But, after so much toil and heartache, even that single point would have felt like a victory, and then came yet another gut-wrenching failure.
"It's difficult to find the right words to express our disappointment, our frustration and, yes, our sadness. So I'll say only this. It's simply, and absolutely, not good enough."
McLaren are in their third of a 10-year deal with Honda, but their relationship is at breaking point, with recent failures harming two of the biggest brands in the automotive world.
In Canada, there was a growing suggestion that McLaren will seek to broker a deal with Mercedes, but the road to doing so will not be an easy one. Honda also have a significant financial hand in Alonso's hefty wages.
The double world champion is out of contract at the end of the season, but has said he will leave if he is not in a position to fight for victories after the summer break in August - a scenario which appears improbable given McLaren and Honda's recent turmoil.
Alonso took to the adjacent grandstand from where his car conked out still wearing his overalls and crash helmet, before launching his gloves to the fans but his presence amongst the Canadian supporters only served to highlight yet another Honda failure.
"I am frustrated, of course, but it's not only about losing a point," Alonso said.
"As a driver, we try to come here and drive as fast as we can, so missing out on that point is disappointing especially for the guys, who have been working so much day and night, preparing the car, preparing the strategy and taking care of every single detail.
"Our chassis feels quite strong in the corners, but we are being overtaken by everyone in the middle on the straights. It's tough times."
