Stoffel Vandoorne has said that he will remain race-ready ahead of next weekend's Chinese Grand Prix.

Although Fernando Alonso was getting CT scans done early last week, the Spaniard's chest injuries clearly caught McLaren by surprise once in Bahrain.

That is because when the FIA ruled him out of action on Thursday, reserve driver Vandoorne was thousands of kilometres away in Japan, testing his Super Formula car.

"At the beginning of the Japanese season there are only four days of testing, which is why we sent him there," McLaren team boss Eric Boullier is quoted as saying by Auto Motor und Sport.

"The [Super Formula] series is important for him as he needs to stay race sharp."

Now, the Belgian rookie will need to be race-sharp again, as Alonso cannot get the green light to return next week in China until follow-up examinations by the FIA.

"I will be in the simulator tomorrow so I am a little calmer for the weekend," Vandoorne told Belgian radio Sporza.

"Next week I will go to China and we'll see if I'll be in the car or not."

Asked what his chances are, Vandoorne answered: "It's very difficult to say. Fernando will have more tests after the weekend and then a decision will be made.

"After my first race weekend, it won't be easy for me to be back on the sidelines, but I knew that's what my situation would be like this year.

"Perhaps the race in Bahrain was my real test. I think I proved that I'm definitely ready for it. I made a good impression on the team and the F1 world, which can only help me for the future."

Vandoorne finished tenth in Bahrain.