Everything Ferguson, Allardyce and Keane said about Ronaldo's 2003 Man Utd debut

Cristiano Ronaldo is awaiting his second Manchester United debut after re-signing for the club, following a 12-year spell away from Old Trafford.

The Portuguese star originally signed for Sir Alex Ferguson's side in 2003 from Sporting Lisbon for £12.25million, and spent six years in Manchester before heading to Real Madrid.

Ronaldo left as one of the best in the world, and established himself at Madrid as one of the all-time greats before enjoying a three-year spell at Juventus.

The 36-year-old returns to sign off a glamorous career, but no one could have expected the success that would follow from his original United debut against Bolton in August 2003.

Cristiano Ronaldo starred after coming off the bench against Bolton ( Image:

ADRIAN DENNIS/AFP via Getty Images)

Ronaldo was placed on the United bench for their Premier League season opener against Bolton, and was introduced on the hour mark after Ferguson was frustrated with his sides performance in the game so far.

United led 1-0 thanks to a Ryan Giggs free kick, but three more goals followed after Ronaldo's introduction as the teenager changed the game, inspiring his new side to a 4-0 win in front of his new fans.

Ferguson said that Ronaldo left the field as United's "new hero", and spoke about the new signing's impact, saying: "It was a marvellous debut, 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."

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Cristiano Ronaldo is back at Manchester United after 12 years away ( Image:

Getty Images)

Although his side had just lost 4-0, Sam Allardyce also praised United's new signing, as the Bolton boss said: "He was different class, he looks a very exciting player and his introduction was crucial."

Allardyce also admitted he had hoped Ronaldo wouldn't make his debut against his side after he shared a conversation with striker Mario Jardel, who was a former teammate of the Portuguese star at Sporting.

The Bolton boss revealed: "After what Mario told us we were hoping he wouldn't even be on the bench. 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."

Despite the high praise from Allardyce and Ferguson, former teammate Roy Keane admitted he wasn't overly impressed during Ronaldo's debut, as he said: "It was 20 minutes, that's all it was. I think he won a penalty, but so what?"

Although Keane is never one to shy away from controversy, his comments were purely based on the extremely high standard that he expects, and the Irishman is well known for his admiration for Ronaldo.

Keane recently said following the Republic of Ireland's defeat to Portugal: "How many times can I say it? The man's a genius. I'm sick of saying it."

Ronaldo scored twice as Portugal won the World Cup qualifier 2-1, and the United star became the all-time mens international goal scorer as he netted the winner deep into injury time.