McLaren are remaining positive about Fernando Alonso's Indianapolis 500 hopes despite failing to run on Thursday.

Following the Spaniard's first crash at the Brickyard on Wednesday, the British team spent yesterday repairing his car after substantial damage was caused.

Then, just as Alonso was ready to hit the oval, heavy rain caused practice to be halted, leaving the double Formula 1 champion just one more day before qualifying on Saturday.

“It’s definitely slow going,” McLaren CEO Zak Brown admitted.

“We had to borrow pieces from the one car and move them to the other car, bring in bits from an outside location, change the engine. It’s been a lot of work.

“We’re just trying to get it done right, put some extra TLC in it and make sure it is ready to go.”

Given Alonso's preparation has been hit by reliability worries as well as the crash, there are some questioning if he'll make the first hurdle of making the start grid on May 26, as 36 cars go for 33 places.

“I’ve seen lots of drama here before, and I don’t want any drama,” Brown added.

“The speed in the car (Wednesday) seemed to be OK, Fernando will get right back up to speed, he’s not fazed, so I think we are just trying to put together a car that is ready to go and ready to perform.