Lord Alan Sugar has undergone knee surgery.

Lord Alan Sugar

Lord Alan Sugar

Following last week's launch of the 15th series of 'The Apprentice', which starts on BBC One tonight (02.10.19), the 72-year-old businessman went in to have the op.

According to the Daily Mirror newspaper, he rubbed his right knee and said: "I'm straight off to hospital now."

The 'Apprentice' star underwent a three-hour procedure on the same day.

He wrote on Twitter: "Game ready, amazing machine for rehabilitation after a knee replacement."

Lord Sugar had the operation last week to fit in around his many commitments.

The former Tottenham Hotspur chairman also survived a heart scare a couple of years ago, when he suffered a blocked artery. He made the discovery after completing a 25-mile bike ride with wife Ann.

He said at the time: "She came with me and said, 'What are we doing wasting our bleeding time here? You are a bloody hypochondriac. There is nothing wrong with you.'

"Anyway I go and have this thing and see the doctor, who is reading the scans, and the pair of us nearly passed out because he said to me, 'You better go straight to A&E."

Despite the health scare, Lord Sugar insists he has no plans to stop working.

He said: "I'm very, very fit for my age and have a good healthy diet and regular checkups. Age doesn't bother me.

"I won't retire!"

Lord Sugar recently admitted he is keen to do continue on 'Apprentice' for another five years, which will take him to 20 series.

He said: "I'm only contracted to do one more, but I might do up to series 20. That sounds like a nice round figure."