Martin Whitmarsh wants to quickly forget McLaren's Canadian GP weekend, which saw the team's 64-race run in the points come to an end.
Although Montreal has often been McLaren's circuit in the past, this weekend it was anything but.
The faltering outfit failed to make the most of the wet conditions in qualifying with neither driver making it into the top-ten shoot-out.
Sergio Perez and Jenson Button were also unable to recover in the dry on Sunday, finishing P11 and P12 respectively.
The team's lack of points brought to an end a streak of 64 grands prix inside the points.
"A weekend that we'll try quickly to forget," Whitmarsh told Sky Sports F1.
"Qualifying was poor and then in the race, looking back at it now, we made mistakes. We weren't quick enough, that's the starting point, but I think we should have been able to get into the points.
"The prime tyre was the much better tyre than we believed it was, we wished we started on it now and wished we got onto it sooner. Also when we put Jenson onto it, we gave him a relatively slow target lap as we were concerned about getting him to the end, but as it turned out he could have pushed a lot harder."
The team remains sixth in the Constructors' Championship but lost ground to Force India, who brought both cars home in the points.
Asked if McLaren's latest stumble would once again lead to him revising the team's targets for the season, the team boss said: "Of course you are but we've got to get the car quicker.
"We've got to keep working hard, it hasn't always been as fruitful and as positive as we wanted to, but there's no secrets unfortunately, there's no magic wand.
"We've got to work hard and make the car quicker and make sure that we come through qualifying sessions better than that and do better in the race.
"Both drivers are driving well but we're not giving them quite the car that they need to get the job done and we're not quite making it work in qualifying or the race - certainly this weekend."
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