Celtic failed to sign Scott McDonald before he went on to be pivotal in the action on the day we lost the league in 2005.
The former Hoops striker told Four Tims and a Podcast that the club wanted him on trial from Australia.
But, Southampton had offered Skippy a permanent contract and his decision was made.
McDonald would later leave the Saints and join Motherwell, where he stopped the Celts winning the league.
Celtic offer trial to Southampton bound Scott McDonald
The 36-year-old is a Celtic fan from birth with both of his parents hailing from Scotland.
McDonald rose up through the youth football ranks in Australia which alerted a few clubs in the UK.
Southampton were the front runners due to an offer McDonald couldn’t turn down.
McDonald told the podcast that he did receive a call from Celtic’s Willie McStay out of the blue.
McDonald said: “He said ‘hello, it’s Willie McStay, we would like to have your son over and have a look at him at Celtic’.
“At that time I’d already agreed my deal with Southampton and Celtic only wanted to have a look at me rather than have a contract in place.
“At that point we thought it would be best for me to go with what was already there as I had a risk of losing that if I had chosen to go to Celtic.”
McDonald would go on not making an impression with the Saints and was loaned out twice before joining Motherwell.
Skippy on feelings after decisive title day
McDonald halted Celtic winning the league title on the final day in 2005, by scoring two late goals and winning the match.
Skippy, the boyhood Celtic fan, reflected on how he felt following the game in the changing room.
He said: “In the changing rooms I was s** scared – proper s*** scared I was going to get done in.
“I was thinking what is everyone else going to think of me – family, friends, the lot.
“At that moment in time it’s just a switch and you’re not thinking straight at that point at the time.
“It’s easy to go an pinpoint me and blame me for everything as a Celtic fan.
“If they watched the game back they’ll see faults in their own team and why they didn’t win that football match.”
McDonald signed for Celtic in 2007 and went on to have a stellar career, scoring on his home debut.
He cited Gordon Strachan as a big influence on his career and left for England with him in 2010.
McDonald is now back in Australia with Brisbane Roar, scoring three goals in seven so far this season.