Cristiano Ronaldo's training ground obsession developed groundbreaking move

For more than 15 years, football fans have witnessed Cristiano Ronaldo score outrageous free-kicks from all angles.

The Portuguese icon's unique knuckleball technique has bamboozled goalkeepers from across Europe. It didn't come naturally to him, however.

As former Manchester United stopper Luke Steele reveals, Ronaldo worked tirelessly on the training ground to perfect his trademark strike.

"The training field and the gym is where I saw a young lad who was the best player in the world in the making," said Steele, who now runs the Youth Dreams Project.

"I didn't know he was going to be the best player in the world and win five Ballon d'Ors, but looking back now I can see that he was [going to become the best].

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"He was hardworking, like everybody was at the club at that time, but he did extras. He always wanted to stay out with me or the other goalkeepers and practice that free-kick.

"I can honestly say that he wasn't particularly great at that free-kick, I'm sure he would say that himself at the age of 18, 19.

"I always remember Louis Saha teaching him something - I don't know what they were muttering about - but often the ball would fly into the car park which was just behind at Carrington.

"I'd even be thinking, 'Flipping heck, hit the target because I'm getting cold here.' But gradually he just adapted... all of a sudden he started hitting this free-kick that started wobbling and moving all over.

"That was something that hadn't really been done, or I hadn't seen a great deal of it.

"He was just a phenomenon. He was against top defenders every day in training - people like Mikael Silvestre and Rio Ferdinand - and that made him stronger and adapt his game.

"Every game he just got better and better."

Another goalkeeper who practiced free-kicks with Ronaldo was Tom Heaton. The England international made his United debut against Young Boys on Wednesday evening, 19 years after first signing for the club.

Heaton and fellow ex-United youngster Paul McShane, who is currently working with the U23s as a player-coach, both returned to Old Trafford last summer.

And Steele is delighted to see his former team-mates represent United again. "I lived in the digs next to them, Paul and Tom are really good friends of mine.

"I actually went to Old Trafford last week for the first time in 15 years, Tom sorted me out tickets, and to see him there was such a joy.

"I know the hard work he's put in, I know it took ages for him to get his career started, but for him to go back to the club where he started... it's great and he deserves it.

"I know he's not going to get a lot of game time because you've got [David] de Gea and [Dean] Henderson there, but it's brilliant.

"For him to play the other night was just great. A proud moment for him and his family and I'm more than happy to say Tom is one of the most hardworking goalkeepers I've ever met.

"And that goes for Paul as well. Paul is one of those guys that when we were younger we said, 'He'll be a good manager.' You know when you just have those characters.

"Paul could be a really, really top manager and one of his best assets is his ability to adapt and he's doing the right thing.

"This U23 role is something new, but he's going to be learning through the academy while still playing and, whether it's a managerial job or coaching job, I think he can be terrific in years to come."