Indeed, the previous campaign the midfielder netted his maiden goal during a final-day 3-0 triumph over Barnsley to remain in the First Division.
Then, in March 2002, the prodigious talent was introduced to his fifth permanent Blues manager – Harry Redknapp.
Named in the former West Ham boss’ maiden Pompey team, the outcome resulted in a 2-0 defeat at Preston, during which Svetoslav Todorov was dismissed.
O’Neil accompanied Redknapp for much of those glorious times.
And, 20 years after that pivotal appointment, he recognises Redknapp as the finest manager he played under.
The 38-year-old told The News: ‘I saw Paul Merson on Sunday, my little boy was playing football and his boy was in the same place.
‘We had a chat and Merse was saying how next year is 20 years since we won promotion. It’s truly incredible how that has gone so quickly.
‘My favourite spell of my career coincided with Harry being appointed Pompey boss – and the favourite spell of his own managerial career.
‘It was probably a favourite spell in a lot of people’s careers, if you ask them.
‘I know Paul Merson would have had highs at Arsenal but I know he looks back fondly on that season, Linvoy, Matty Taylor, probably so many others.
‘You go onto other things afterwards, but if you think back through your top five or six days as a footballer, a good fair few of mine were in a Pompey shirt.
‘And I’m sure a lot of the boys from that group would say the same.
‘Before Harry, we were struggling along, avoiding relegation, and although there were some good signings, there weren’t many who were proven. Courtney Pitt, Neil Barrett, Peter Crouch, players you hoped might be able to help, but not proven.
‘Then Harry came in and he was never going to let it be a failure. He wouldn’t let that happen to himself or his own reputation, you could tell it was too important to him.
‘Suddenly players started to arrive and you’d think “Cor, how did we get him? What’s he doing at Pompey?”.
‘There was one, then we had two of them, and, before you knew it, you’d look at that team and it was full of players easily capable of performing at the top end of the table.
‘The journey the club went on at that point was incredible.’
Under Redknapp, Pompey won the Division One title in 2002-03 to reach the Premier League, and then oversaw them remaining there until quitting in November 2004.
He returned 13 months later to initiate the Great Escape, subsequently taking the Blues to two top-nine Premier League finishes, claiming the 2008 FA Cup and then into Europe for the first time in the club’s history.
Meanwhile, O’Neil was sold by Redknapp to Middlesbrough in August 2007, following 192 appearances and 17 goals.
Bournemouth’s senior first-team coach added: ‘Harry was very, very clever – the best manager I played under.
‘He knew what it took to build a team, to keep a team motivated, and was then ruthless enough to make sure it kept progressing. There was not too much sentiment involved.
‘If we get promoted and you are no longer going to be good enough for Harry, he’d make sure you were replaced because it was important to him that he was successful.
‘For taking a club from where it was to where it arrived, no other manager I worked with would have been able to do such an incredible job like Harry did at Pompey.
‘Others impressed me, Alex Neil at Norwich picked us up off the floor and got us promoted to the Premier League, while Sam Allardyce was excellent at West Ham.
‘But when you base it on achievements and longevity, over a couple of spells at Pompey, Harry is the one I most respect. The best.’
A message from the Editor, Mark Waldron
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