"Clearly we have problems," the American told Sky Sports television after the penultimate day of testing at Barcelona's Circuit de Catalunya brought more breakdowns and red flags.
Belgian rookie Stoffel Vandoorne managed only 48 laps -- not even a race distance and less than a third of that covered by Ferrari's Sebastian Vettel.
"I think Melbourne is going to be tough. I would be surprised if we are where we need to be and want to be by Melbourne. So it's going to be a tough start to the year," said Brown.
The season starts in Australia on March 26 and Brown said the whole team was pulling together to address the issues "so I think crisis would be a bit strong."
Double world champion Fernando Alonso was critical of McLaren's engine partners on Wednesday, telling Spanish reporters that everyone in the team was ready to win 'apart from Honda'.
"We have only one problem, that is the power unit. There is no reliability and there is no power," said the Spaniard, who will be out of contract at the end of the season and has been unable to get much test mileage under his belt.
McLaren have had a torrid time since they renewed their previously successful partnership with the Japanese manufacturer.
In 2015, their first year together, the former champions endured their worst season and finished ninth overall after a spate of power unit failures. In 2016 they had better reliability but still only finished sixth.
The second most successful team, in terms of race wins and total championships, has not won a race since 2012 when they had Mercedes engines.
"We've been given assurances from Honda that they are going to do everything they can to give us the best power unit possible," said Brown.
"But I think in this world it's pretty hard for anyone to promise -- a driver to promise he's going to win or for us to promise to be the best race car or best power plant."
He said McLaren had a long-term contract with Honda and both sides had the right people to make it work. There was no question they would see it out because "that's what McLaren does."
(Reporting by Alan Baldwin, editing by Ken Ferris)
Share
