More from Djokovic: "I always try to imagine myself as a winner. I think there is a power in that.

"It's a constant battle within, for me anyway, more than what happens [physically].

"I told myself to switch off from what was happening around us, and just be there, be present.

"I thought I could have played better, but one thing that allowed me to come back was the mental stability in those moments.

"You need to be constantly playing well for five hours to get through a match like this, but there is a self-belief too."