With 466 laps (1,347 miles) under his belt following pre-season testing, and his team also topping the constructors' and engine manufacturers mileage stats, world champion Lewis Hamilton should be feeling confident as he begins his quest in securing his seventh crown.

However, in the wake of a number of engine-related issues which he and his teammate and Williams suffered, the Briton has expressed concern at the W11's reliability. Indeed, on Thursday, Hamilton was sidelined by an oil leak after just 14 laps.

"It's a concern for sure," he told reporters. "Normally in pre-season testing we're much more confident in the reliability, so it's not been perfect for us.

"I think we're on our second engine already," he added, while Williams is on its third. "It's definitely not an easy or relaxed scenario for us but I have every confidence in the guys back in the factory that they will analyse and do the best they can in the next two weeks to make sure we start off on the right foot.

"It's better than last year's car, which is the same for everybody," he continued. "It's an evolution of last year's car. So we all should generally have more downforce and it just feels like a continuation of what I drove last year.

"I have no idea where we stand compared to others," he admitted, "the team will probably have a better idea than that.

"I don't know where everybody else is, I think I understand the car well so I'm comfortable and confident in terms of getting in the car for Melbourne and knowing that I'll be able to attack and extract the most from it but whether that's going to be enough to be ahead of others, we'll find out."

Check out our Friday gallery from Barcelona, here.