Whatever or wherever he's driving, Fernando Alonso is always a force to be reckoned with says his former McLaren team mate Jenson Button.
The 2009 F1 world champion heads to Le Mans next month with SMP Racing and he'll likely cross Alonso's path at some point during the grueling event as the Spaniard tackles the legendary 24-hour with Toyota.
"He's definitely one of the drivers you worry about," the Briton told Sky Sports News.
"Whatever you're racing in, if he's competing, you're going to worry.
"He's not just quick, he's a very clever driver, he's got the experience and he is always there.
"If you have a great day, you might out-qualify him and you might have a great race but he will always be on your heels. He very rarely has a bad race, which is tough when you're team-mates with him."
As formidable a force he may be, Alonso also brings the best out of his opponents says Button.
"We're going to go into Le Mans racing against each other and I know if we're in a stint together, he's not going to put a foot wrong," he admits.
"It doesn't matter if it's three in the morning or three in the afternoon, he's going to be 100 per cent.
"You've got to keep up with that and it's tough but that's what I love about racing against the best drivers in the world. They keep you on your toes."
Regarding the Spaniard's Triple Crown ambitions - the feat of winning the Monaco Grand Prix, Le Mans and the Indy 500, something achieved only by the great Graham Hill - a Le Mans win for Button would put him one up on Alonso.
But a run at the Indy 500 is out of the question he insists.
"I'm going to leave that one for Fernando to do," he said. "This is pretty much the busiest season I've had in my career."
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