Roy Keane insists he will not be rushed into making a decision about his future.
After gaining the 'closure' he was looking for from his testimonial game at Old Trafford last night, the veteran midfielder will spend a short holiday with his family before meeting his surgeon and deciding whether he is fit enough to continue his career at Celtic for another season.
Hoops boss Gordon Strachan has left a one-year offer on the table for Keane to consider.
But, while the 34-year-old claims he has made no definite decision about his short-term future, the indications are that he will call time on an illustrious career.
'I realise my heart could be telling me one thing and my body another but I am quite relaxed about the situation,' said Keane.
'I don't feel too bad but equally I do not feel as though I have done myself justice at Celtic.
'I have suffered one or two niggling injuries, which could have been influenced by the amount of travelling I have been doing and also a torn hamstring which I am certain came about because of my hip operation.
'Nothing is definite yet but if I am suffering niggling injuries all the time, that is no use to anyone.'
Keane's popularity at both Manchester United and Celtic was shown by a near 70,000 crowd which will net around £2million for the Cork-born star's favourite charities.
The occasion proved to be far more enjoyable than Keane thought possible, although he did regret the absence of old friend Ruud van Nistelrooy, who was effectively banned from playing by Sir Alex Ferguson following the pair's massive bust-up prior to Sunday's Premiership game with Charlton.
Van Nistelrooy revealed missing the game was the most painful aspect of the row with his manager as he was looking forward to once again turning out with the man he defended following the infamous MUTV tirade which heralded Keane's own exit from Old Trafford.
'I did speak to Ruud,' said Keane, whose closeness to the Dutchman is emphasised by the fact Van Nistelrooy has his closely-guarded telephone number in the first place.
'It was unfortunate and disappointing he wasn't here but everyone has their own path to go down.
'I don't think it is right for me to start commenting on Ruud's situation because I am no longer at United and I do not really know the goings on.
'But I did get on quite well with him and I do know there are two sides to every story. Maybe one day we will find out what happened.
'Ruud is still under contract to United and I wish him well.'
Ironically, the man Van Nistelrooy is said to have rowed with in training, Cristiano Ronaldo, netted the only goal 10 minutes into the second-half.
By that time, Keane had switched from the green of Celtic to the red of United, so could technically claim his last appearance for United was a winning one.