Yet, for him, one name stands out – Paul Merson.
It was 20 years ago today when Redknapp replaced Graham Rix as Blues boss, with a teenage O’Neil selected in his first line-up for a trip to Preston.
The hard-working midfielder would subsequently play alongside Shaka Hislop, Arjan De Zeeuw, Steve Stone, Yakubu, Teddy Sheringham, Sol Campbell, Kanu, Benjani, Pedro Mendes, Niko Kranjcar, Sylvain Distin, Matt Taylor, Hermann Hreidarsson and Glen Johnson.
O’Neil told The News: ‘In my time at Pompey, Paul Merson was Harry’s best signing.
‘It was the impact he had on the club, he was the catalyst, helping it jump into something it hadn’t been for a long time.
‘There may have been better signings later on down the line, Sol Campbell was absolutely incredible in training, it was ridiculous to have somebody like him at a club like Pompey, while Yakubu was incredible.
‘I never played with Lassana Diarra, but how they managed to get him I will never know. Who moves from Pompey to Real Madrid? It’s unheard of.
‘But, for me, Merse was the vital catalyst to what happened after that.
‘We would have still got promoted without one or two of the others, whereas I’m not sure whether we’d have managed to get over the line if you took Merse out.
‘He missed some games with a bruised foot, having injections for a while, and I just remember whenever he wasn’t in the team it felt very different.
‘Merse was always nice to me, although was quite ruthless with some of the other lads. If you couldn’t control the ball and pass it to him very well, then he wasn’t a big fan of yours! He would let you know.
‘But he seemed to believe I was capable of doing what he needed me to do, so was always fairly complementary.
‘I was never on the end of one of Merse’s little rants, he was always very positive, maybe because of my age or maybe he thought I was half decent. He was really good for me.’
And O’Neil, who is senior first-team coach at Bournemouth, marvels at Redknapp’s man-management ability during unforgettable Pompey times.
He added: ‘As a manager, it wasn’t just picking 11 players, making substitutions and choosing whether to go three or four at the back. There was so much more than that with Harry.
‘I honestly believe Harry's best work was done away from the pitch in getting these players to come and the way he ran the club.
‘Keeping those boys happy and content at a club like Pompey was incredible.’
A message from the Editor, Mark Waldron
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