Former world champion Jenson Button has reflected on McLaren’s disappointing start to the season four races into the new campaign.

The Brit spent seven years racing for McLaren alongside countryman Lewis Hamilton and then Fernando Alonso and has had his say on his former team's struggles since switching to a Renault engine for 2018.

Before the season started, there were some lofty expectations about the competitiveness of the British manufacturers' car but the 20-time champions have failed to even reach Q3 in qualifying this term as they currently sit fourth, leaving Button to recognise they are some way off the ‘top three’ of Ferrari, Mercedes and Red Bull.

"The three big teams, it's difficult to challenge them at the moment and it's going to take a while," Button told Sky Sports.

“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."

Alonso currently sits sixth in the driver standings however the two-time world champion has failed to improve on his promising fifth place finish which he achieved in Australia, crossing the line in seventh for the three races since.

Given how much Alonso and co. have struggled in recent years, there have still been some very positive steps in 2018. Perhaps they should have set some slightly more realistically achievable targets before the season the started.

On Alonso, who Button will be competing against in the Le Mans 24 Hours race in June, the Brit added: 

"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."