The first rule in motorsport is that you have to beat - or at least come close to beating - your own team mate. On that count alone, Canada was a disaster for McLaren's Jenson Button, who ended up with a 16th place finish in the Grand Prix while Lewis Hamilton went on to a famous victory.
But more worrying still for Button is that he simply doesn't know what went wrong in Montreal.
"I didn't find the speed today," he said. "I don't have an answer. I just didn't have any pace [and] it seemed to get worse and worse. I couldn't look after the tyres; I didn't have any pace, there was nothing there. I don't know why.
"I'm not two seconds slower [per lap] than Lewis," he added. "I'm pushing the car to its limits and I'm one and a half to two seconds off the pace of the leaders - and one is my team-mate."
One of Button's traditional strengths had always been his smooth driving style which is kinder on his tyres than other drivers such as Hamilton. But Canada proved to be totally the opposite, leading to questions about whether there was something going wrong with the 2012 Pirelli tyres
"It's not tyres, I can't be the only person who can't drive the tyres," he insisted. "It's impossible ... I don't know what's going on," he confessed. "I'm confused and very lost."
Button wasn't inclined to sugarcoat the situation or to hide his dismay at how the day had gone: "[It was] probably my worst race for many, many years," he said. "We have to improve it and sort it out sooner rather than later.
"Generally, the past few grand prix weekends haven't been great for me. But every time you make changes to the car, you're hopeful that it's going to go well and give you an improvement, so hopefully we'll be able to solve it sooner rather than later."
Martin Whitmarsh said that the team had to share the responsibility for Button's mid-season slump, after getting off to a flying start to the year in Australia.
"Today was another day on which we, his team, failed to provide him with the tools with which to do the brilliant job we all know he's capable of, and which he did so superbly here last year," said the McLaren team principal.
"He lost track time on Friday through no fault of his own," Whitmarsh added. "[He] was unable to qualify as well as he would have done had he not lost that track time and may have been further troubled today by a suspension set-up, different from Lewis's. That left him with excessive rear tyre wear. We'll have to check that out."