Stoffel Vandoorne thanks Fernando Alonso for help on F1 debut

Vandoorne has been forced to step into Alonso's car this weekend after the Spaniard failed medical tests on Thursday due to chest injuries sustained in his crash during the Australian GP.

Rather than flying home, Alonso has stayed on in Bahrain and has played his part in getting team reserve and reigning GP2 champion Vandoorne up to speed.

"Fernando was here all day," said Vandoorne.

"He's been next to me and the engineers, and he's been very helpful, giving some comments about which direction to go with the car set-up, what to try during the practice sessions.

"It's been very useful to have him here as he obviously knows the car a bit better than me. It's definitely been good to have his help."

Vandoorne has confirmed only receiving his call up from racing director Eric Boullier 10 minutes after Alonso had left the medical centre at 12.30pm local time in Bahrain on Thursday.

At the time the 24-year-old Belgian was preparing for a test session ahead of competing in Super Formula in Japan this season.

It prompted a hasty departure and a lot of learning on the flight across to the Middle East.

"It's been pretty hectic, with a lot of phone calls with the engineers, and a lot of documents I had to go through on the plane from Japan," added Vandoorne.

"They sent me through all the files with all the information I had to know, like the steering wheel, things operationally before the race, what we can say and not say [on the radio]. I spent my time well on the plane."

Although only likely to be in the car for one race, Vandoorne recognises he now has an opportunity to put himself in the shop window for a permanent seat for next season.

Suggested to Vandoorne his drive was an audition for the future, he replied: "I definitely hope so.

"First of all, this is one opportunity I'm getting. I'm very happy to get the chance to race with McLaren this weekend.

"I'll try to enjoy it, I know it's very difficult sometimes when you only get one shot, but I'll do my best and what the result will be it's difficult to say.

"Regardless of the situation the team always looks at how high your performance is, but I'm not really thinking about that at the moment.

"I'm just focusing on this weekend, there is a lot of stuff to go through, so I'm making sure I make no mistakes and bring the car home.

"I'll try to do my best as usual, and we'll see where we end up."

Vandoorne, who had not tested the 2016 McLaren prior to Friday, ended the day 11th fastest and seven tenths of a second behind team-mate Jenson Button.