In the summer of 2003, Manchester United faced Sporting Lisbon in a friendly. It was friendly that would change everything.Sporting ran out 3-1 winners and an 18-year-old Cristiano Ronaldo was the star of the show.Ronaldo was so good that Sir Alex Ferguson later revealed that his players urged him to sign the Portuguese winger on the plane home.Ferguson obviously listened and was soon announcing a £12.25 million deal for the Portuguese superstar, making him the most expensive teenager in football history.Four days later, he was named in the squad to face Bolton at Old Trafford on the opening day of the season - exactly 18 years ago today.Ronaldo was watching on from the bench as United struggled to overcome a stubborn Bolton side.Ryan Giggs’ free-kick had put the home side 1-0 ahead but the Red Devils needed some inspiration. Fergie turned to United’s new No.7 to bring him on after 61 minutes with the score still at 1-0.Cristiano Ronaldo made his Manchester United debut vs BoltonWhat happened next has done down in history.Ronaldo produced an incredible cameo performance during his 29 minutes, helping United eventually win 4-0.With his silver boots and blonde streaks in his hair, Ronaldo’s tricks and flicks wowed the 67,647 inside the stadium - some of which had probably never heard of him.Inside half an hour, Ronaldo had given full-back Nicky Hunt an absolute nightmare, won United a penalty and created a goal for Giggs.What a performance.To mark the anniversary, we want to share an incredible video showing Ronaldo’s every touch from that afternoon.Video: Cristiano Ronaldo's Man Utd debut vs BoltonEnjoy:

Ronaldo’s performance was so good that Ferguson suggested that United fans had a “new hero.”

"It was a marvellous debut, almost unbelievable," added Fergie. "I thought the pace was too slow in the first half and I knew Cristiano would add penetration. We have to be careful with the boy. You must remember he is only 18. We are going to have to gauge when we use him."

Opposition manager, Sam Allardyce, already knew Ronaldo’s qualities after speaking to Bolton striker, and former Sporting Lisbon teammate, Mario Jardel.

”After what Mario told us we were hoping he wouldn't even be on the bench," Allardyce said. "He reminds me of Ryan Giggs when he first started. He can go inside, outside, uses both feet and runs at people. Everyone holds their breath when he gets the ball."

However, the best praise was dished out by another legendary No.7, George Best.

”It was undoubtedly the most exciting debut performance I've ever seen," said Best. "There have been players who have some similarities [to me], but this lad's got more than anyone else, especially as he is genuinely two-footed. He can play on either wing, beat players with ease and put in dangerous crosses with his left or right peg. When was the last time you saw that?"

The ultimate Cristiano Ronaldo quiz

What happened next?

Well, Ronaldo didn’t do too badly in his years at Man United as he won three Premier League titles, two League Cups, the FA Cup, the Club World Cup and the Champions League. He scored 118 goals in 292, picked up the Ballon d’Or which earned him an £80 million move to Real Madrid.

In Spain, he scored a ridiculous 450 goals in 438 appearances, landed four further Ballon d’Ors while winning another four Champions Leagues.

Nine seasons at the Bernabeu was followed by a €100m move to Juventus, where he has since scored 101 goals in 133 appearances and winning two Serie A titles.

And it all began back on August 16, 2003 during that amazing 29-minute debut against Bolton.

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