Roy Keane had an illustrious career at Manchester United, but when that chapter in his career ended he chose Celtic over Real Madrid.

At the time, Keane had said goodbye to a 12 and a half years at Manchester United and had offers from Real Madrid, Celtic and Everton.

Keane was 34-year-old at the time and closing on the end of his career he wanted to go out with a bang – so he chose Celtic and made his debut on January 14th 2006.

The current Ireland assistant manager made 10 appearances in four months for Celtic, scoring once against Falkirk, but had to cut his time short at Paradise due to injury.

As quoted by the Belfast Telegraph , he said:

Celtic came in, I spoke to Everton, Real Madrid offered me a year and a half and at 34 would I go to Spain for a year and a half? I had doubts in my own head. Self-doubts do creep in with the injuries and would I want to go abroad with my family?

The Celtic move was a bit of a treat for me. Gordon Strachan didn’t really need me because he had Neil Lennon and Stiliyan Petrov but when I went to Celtic what I wanted to do was play against Rangers. I fancied that one game.

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Keane got his wish and played in two of the former Old Firm derbies against Rangers, including a 1-0 win at Ibrox in February.

He also reflected back on his time at the club and was very honest about his time at the club.

I was travelling from Manchester to Edinburgh on a plane, hiring a car and driving to Glasgow to train. My own preparation at Celtic wasn’t great. I have got to be critical of myself.

Trust me getting a flight in the morning and then travelling by car to Glasgow at seven in the morning wasn’t good and then I tore my hamstring twice up there.

I still had a year left of my contract at Celtic but that summer I was on holiday and I thought I had had enough.

Gordon didn’t try hard to persuade me otherwise and that was it, game over. Even though it didn’t work out I’m grateful that I had the chance to play for Celtic.

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Keane did reject the Celtic job before they appointed Ronny Deila, and could be a candidate in the summer if the club decide against renewing the Norwegian’s rolling contract.