Eric Boullier believes that
McLaren "have to be ambitious" and "have to tale risks" if they want to return to the sharp end of the Formula One field.
Boullier says McLaren were right to be aggressive during the two winter tests despite reliability problems.
McLaren only managed 599 laps over the eight days, the lowest of any team.
Despite this, Boullier says McLaren reacted well to their problems on Friday, with good pace and mileage from the team.
Boullier said: "If you want to be competitive you have to be a bit aggressive and have ambition.
"Is it too much? I don't think so, we just have to make sure that with this strategy, we have to leave ourselves enough time to do everything.
2The last three years were difficult. We are now trying to get McLaren back to where it should be.
"Like anything, you don't do it in one day. There may be a few glitches.
"We have not lost our capability of designing fast cars and I hope you will see it on-track soon.
"We have to be ambitious. To be ambitious we have to take risks."
Fernando Alonso recorded the second fastest time on Friday's final day of testing, only behind Sebastian Vettel in his Ferrari.