McLaren racing director Eric Boullier has admitted that the team are preparing themselves for a difficult to start to the new Formula 1 season.
The Woking-based constructor has been beset by problems with reliability in winter testing and have regularly failed to match the test mileage of their rivals.
McLaren also saw new driver Fernando Alonso taken to hospital following a high-speed crash in Barcelona, and Boullier admitted that those problems will likely mean that the team will be playing catch-up at the start of the 2015 campaign.
"Looking back at the last four weeks, our winter test programme has been difficult," he told reporters.
"However, that wasn't entirely unexpected. This time last year, we saw many teams in a similar situation when they introduced new power units for the first time. This year, we also had the added complexity that very tight packaging brings.
"In overview, the lack of mileage means we won't be as ready as we'd have liked, but we can take away the positive that all the running and data gathering we've done have confirmed that we're achieving the targets we set ourselves."
McLaren are without a race win since Lewis Hamilton's final victory for the team in 2012 at the United States Grand Prix.