McLaren has revealed that part of an upgrade package scheduled for Melbourne was delayed because of the reliability issues encountered by the team in pre-season testing.
The Woking-based outfit was banking on several updates and new components to boost its performance in Australia.
McLaren racing director Eric Boullier has indicated however that the missing specs - which include a new bargeboard design worth several tenths of a second a lap - will likely appear on its car in Bahrain next week.
"We were obviously not prepared for Barcelona and I'm glad we fixed the reliability issues for the weekend," McLaren racing director Boullier told Motorsport.com.
"But during the last few weeks [before the race] we spent our energy fixing the reliability issues and not bringing the upgrade faster to the track.
"So we are going to have another batch coming in Bahrain, which should have been in Australia."
Boullier believes the team will have caught up with the implementation of its development work by the first European race, the Spanish Grand Prix.
Overall, the Frenchman was pleased with the team's performance last weekend at Albert Park, but insists a solid potential for improvement is in the works.
"We are happy with the correlation, so we have not lost what was one of the strengths of McLaren last year," he said, speaking on how the MCL33's track performance measured up with factory simulations.
"That's one of the reasons I guess why Fernando was supportive and happy this weekend, because we have lots of things coming that have been signed off already.
"We are now going to push to make sure we can bring things as soon as possible."