Former McLaren driver Jenson Button is excited to compete against former team-mate Fernando Alonso at the Le Mans 24 Hours. The 2009 world champion has admitted that Alonso is always a force to be reckoned with.

The former teammates will debut at the prestigious race in June, at SMP Racing and Toyota respectively. The Spaniard is juggling his World Endurance Championship campaign alongside his F1 duties with McLaren.

Button was Alonso’s team-mate at McLaren for two years before retiring at the end of 2016. The Briton has praised the 36-year-old and called him one of the best drivers in the world.

“He’s definitely one of the drivers you worry about,” said Button, “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.”

Even though both drivers will be rookies at Le Mans, Button knows that Fernando Alonso will not put a foot wrong.

“It doesn’t matter if it’s 3 o’clock in the morning or 3 o’clock 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.”

Alonso’s WEC challenge is part of his attempt to achieve the ‘Triple Crown’. He has already won the Monaco Grand Prix, twice, the Indy 500, which he attempted last year, and this year, it is the 24 Hours of Le Mans.

Button even advised caution against overconfidence in terms of challenging the Big 3 F1 teams. “The three big teams, it’s difficult to challenge them at the moment and it’s going to take a while,” he explained.

“McLaren came out last year and this year and said they think they might have the best car. It’s a tall order to have the best car in Formula 1 when you’re racing against Ferrari and Mercedes and Red Bull. And I think we’ve seen that isn’t the case.

“So you’d say the season so far is a disappointment but if they didn’t say they had the best car you’d say it’s a great season for them. They’ve made good steps, they’re fourth in the constructors’ standings, but because of what they said at the start of the year you say maybe it’s not what we expected.”