Manchester United legend Gary Neville has opened up on the hobby he was forced to hide from former manager Sir Alex Ferguson.

Sir Alex was notoriously strict on minimising distractions and making sure his players prioritised football. But Neville admits he was 'hooked' on property development from the age of 21, and used to take special measures to hide his business ambition from the Scotsman.

"I knew that it would be deemed a distraction," Neville told The Times. "For me, my football was everything. But distraction was absolutely illegal at United, you know that. You could not be distracted by anything."

As a result, Neville concentrated his property development projects in or to the north of Bolton, which sits above Manchester, in the hope that it would throw Sir Alex off the scent given that most players live to the south of the city.

He would also use the name of a trustee, rather than his own, on company documents in case the manager or his spies came snooping around. While other Red Devils stars were playing golf on their days off or cards on European away days, Neville was focused on building his empire.

"I was going up on site every afternoon, after training," he continued. "I don’t know what other lads did. But I would go on site, spend time in the design team meetings, sit in on the construction meetings, and make sure that I was in cost meetings, bank meetings, sales meetings.

"I loved every aspect of it. I used to bring the architects’ drawings with me in the bag for the plane on European trips. I wouldn’t read them before the game but you can’t sleep after; you’re wired.

"I’d make sure no one was sitting next to me and then get them out and start looking at the drawings, the designs and all the things that I needed to do. For ten, 12 years, I had this almost double life."

Neville retired in 2011, aged 36, with more than 600 United appearances under his belt. The former England international's net worth is estimated at £70million, and his company, Relentless Developments, employs around 700 people.

"I knew that my football career would one day come to an end, and I knew that I had to plan for that," explained Neville, who balances Sky Sports punditry and co-commentary with his work commitments. "I had this thing, at 36, that the second half of my life had to be better than the first half. That was the ambition."