Dario Franchitti, Britain's three-time Indianapolis 500 winner, has warned Fernando Alonso that there will be no margin for error when he tackles the famous Brickyard later this month.
Alonso, who was handed his first taste of IndyCar action earlier this week in a private test, will miss the Monaco Grand Prix to take part in the 500-mile race in America on 28 May.
But it is a race in which drivers reach average speeds of nearly 240mph, and that will not come without risk. The IndyCar series has proven to be one of the most dangerous motor racing categories in recent times.
British driver Justin Wilson was killed after he was hit by debris during a race in 2015, while Dan Wheldon, another Briton, and one-time Indy 500 winner, died following a horrific 14-car pile-up in Las Vegas in 2011.
Indeed it is understood that Jenson Button - a contemporary of both Wilson and Wheldon during their early racing years, has no interest in taking part in the Indy 500 on safety grounds.
And Franchitti (pictured), forced to call time on his glittering career following a crash in which he suffered a broken back, told Alonso there will be no room for mistakes.
"Fernando is a racing driver and the fact that he wants to complete the triple crown, I applaud that," said the Scot, 43. "But it is IndyCar and the margin for error is tiny.
"He will see that as a challenge. It will definitely heighten his senses when he gets out there, but I see it all as positives."
Alonso missed last year's Bahrain Grand Prix as a result of his enormous shunt at the previous race in Melbourne. The 35-year-old Spaniard also sat out the season opener in Australia in 2015 after he crashed in pre-season testing.
Zak Brown, McLaren's chief executive officer, and the brainchild behind Alonso's appearance at Indianapolis, insists there is no cause for concern.
"Motor racing is a dangerous sport and Fernando has been injured twice in our car," American Brown said.
"The Indianapolis Speedway has been a very safe place for a couple of decades now.
"Fernando is extremely prepared, the car is exceptional, and he is going to have a good amount of testing because of the format.
"If you don't want to take a risk you probably shouldn't be in motorsport. We are very comfortable with our decision and so is Fernando."
Two million people watched Alonso complete his first test in Indianapolis which was streamed on YouTube.
But despite the heightened interest in this year's race following Alonso's invovlement, IndyCar chief Mark Miles has no plans to raid the Formula One grid for in future years.
"It is not a strategy for us," Miles said. "Fernando coming was a unique set of circumstances in so many respects so we are not going to be following the grand prix series around and try to poach drivers.
"I am sure more drivers will pay attention to it, and there will points in their career where it would make sense, but it is not our strategy, per se."
