Three-time Indianapolis 500 winner Dario Franchitti was "amazed" by Fernando Alonso's performance in his first I༺ndy car test last week.

Alonso stunned the motorsport world by announcing last month that he would beꦿ skipping the Formula 1 race iꩵn Monaco this year to enter the Indy 500 with McLaren, Honda and Andretti Autosport.

The two-time F1 world champion got hꦿis first taste of both an Indy car and oval running on May 3 at Indianapolis Motor Speedway, passing the Rookie Orientation Programme with flying colours.

While Franchitti believes oval racing will feel unnatural to Alonso given he has spent his entire career ra💖cing on traditional road and street tracks, the Scot was impressed by the Spaniard's first outing.

"To drive an oval is a very unusual thing for a road course driver, someone that's grown up racing on road and street courses, and not o💟n ovals," Franchitti said.

"And Indianapolis is even mor🅘e so a law unto itself. The good news is there's a lot of days of practice. If it rains, that could change things a little bit. Every lap Fernando is going to get is going to be helpful.

"I was amazed, I thought he got up to speed incredibly quickly. I sat and watched the whole rookie t𒐪est and everything. I thought he got up to speed well and did a great job.

"On the plus points, he's with a great team, great teammates asꦅ well, they're going to help him which I think he'll find quite unusual as the teammates are there to help. You want to beat your teammates, but you all work together to beat the opposition because the cars are essentially the same and it's how the teams figures out the small differences that can make the difference between success and failure."

Speaking f🍬rom his own experiences of running in the '500, Franchitti - winner of the race in 2007, 2010 and 2012 - said that it will be the race itself that is﷽ the biggest challenge for Alonso to overcome.

"The toughest thing I found at the speedway at Indianapolis was how to race," Franchitti said. "To run on your own was not that difficult. I🎃t's when you get into the pack and how to position your car. Some of that come💙s from experience.

"When the person in front moves his car inꦯ a certain position, where you do position your car. Then you've♍ got guys beside you and all those sort of things, and how you time your passes, keep momentum up. All those things are going on.

"The weather's going to change a lot. When the weather changes at the speedway, when you look at it, it's four lef💮t hand corners, you think what's the big deal. The weather changes, the temperature changes, the humidity changes, the wind direction changes, and it completely changes the shape of the track and how the track feels.

"He's got all of that going on, and then there's the mental aspect o꧒f being in the car for all those days, and every time you leave the pits you're circulating at above 225 mph, and there's absolutely no margin for error.

"It's the ti♔ghtest of tightropes, and you cannot step over, because you step over, that lovely SAFER barrier is🦩 there waiting."

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