Now it is time to return the captain’s armband to fit-again Brett Pitman.
And the stand-in skipper has relished the brief opportunity to lead the Blues into battle.
Despite being on loan at Fratton Park and amounting just seven league appearances, Kenny Jackett opted for O’Keefe as his temporary captain.
Following Pitman’s knee operation, the responsibility was passed onto the 26-year-old for the away win at Gillingham and then the visit of MK Dons.
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With club vice-captain Gareth Evans recalled at Doncaster, O’Keefe relinquished the duty – albeit until half-time when the winger was substituted.
That meant last weekend’s trip to Blackburn represented three-and-a-half matches as skipper for the Cardiff loanee.
With Pitman expected to be back in the side against Bradford on Saturday, the armband will return to more familiar surrounds.
But O’Keefe has revelled in what he considers to be a tremendous honour.
He said: ‘Obviously, it’s a young squad so I’ve tried to play my natural game and help and encourage people, talking, organising and leading the team on.
‘It’s the first time I have been captain for league matches.
‘Previously it happened with the under-23s at Cardiff and Palace but that’s it.
‘So it’s something I have really enjoyed – and it has been an honour.
‘We are a young team and we need a bit of vocal on the pitch, a bit of voice, a bit of bite.
‘I think it is key, there are so many games at this level there’s not much in it, so any edge you can get is important.
‘It’s nice for the gaffer to put his faith in me, I’ve not been here that long so if I’ve made an impression and created positives then that’s great.
‘I like to think I encourage and organise. If people need a bit of a kick up the backside then I can give it and add experience and knowledge.
‘This is a really talented group of young boys and, with a bit of guidance on the pitch and confidence, we can really achieve something.
‘Brett is club captain and I am sure he will now get it back. But I have thrived off it, it’s been fantastic.’
O’Keefe joined Pompey on deadline day in a loan until the season’s end.
He has made 12 appearances and netted once.