Spanish driver Fernando Alonso crashed heavily during the third practice session for the Indy 500 race, but escaped injury.

He lost control of his McLaren car after hitting a wall.

It was the second major setback for the double F1 champion after he was sidelined for much of the second practice session on Monday with an electrical issue on his car.

“Mistake from my side underestimating the grip in T3 today. I’m sorry for the team and the guys that have to work a lot now. Lesson learned. We will be back stronger later today or tomorrow,” Alonso wrote on social media.

“It was pure understeer on the car, even if I lifted the throttle on the entry to the corner it was not enough and I lost completely the front aero. The wall came too close and too quickly. Unfortunately, it happened today and we will lose some running time again. Yeah, I am sorry for the team but hopefully we will learn and come back stronger tomorrow.

Alonso was 16th on the timing screens having recorded a best lap of 225.433mph.

The Spaniard is hoping to win the Indy 500 to secure the 'triple crown'  - winning the three most prestigious races, the others being the 24 hours Le Mans which he won last year, and Monaco Grand Prix, which he won twice. 

The Indy 500 is on May 26