It is a fixture that Pompey fans have become pretty used to over the past decade.
And the latest chapter of meetings with Oxford is about to be written at the Kassam Stadium this evening (7pm kick-off).
There were four clashes last season – and that was even with Covid-19 cancelling a scheduled trip at the end of March.
And all of them finished level after 90 minutes, but it was United celebrating in the play-offs after Cameron McGeehan’s saved penalty proved costly in the shoot-out.
Karl Robinson’s side then suffered their own heartache at Wembley, with Wycombe beating them to secure the final spot in the Championship.
After a slow start to the current campaign, Oxford have stormed up the table in recent weeks and currently sit eighth – four points behind the Blues with a game in hand.
They have been beaten just once in League One in 2021 and won nine of their past 11 fixtures, although were held to a goalless draw at Ipswich last time out.
United were also denied a spot in this term’s Papa John’s Trophy final after losing their semi-final contest with Tranmere a week ago.
It finished 1-1 when the sides met at Fratton Park back in November, with an Alex Gorrin penalty cancelling out Sean Raggett’s opener.
James Bolton is out with the ankle problem that saw him sidelined at the weekend, but Alex Bass (leg) and Michael Jacobs (hamstring) are both back in light training.
Sam Long could return from a hamstring injury for the hosts, although Oxford will be missing Marcus McGuane (thigh) and John Mousinho (knee).
VIEW FROM THE DRESSING ROOM
Read the thoughts of assistant manager Joe Gallen ahead of the game.
HEAD TO HEAD
Pompey: 25 wins
Oxford: 23 wins
Pompey: 8 wins
Oxford: 19 wins
Referee: Graham Salisbury
Assistants: Stephen Brown and Greg Read
Fourth Official: David Rock
Supporters in the UK can watch the action live – with graphics, commentary and replays – by purchasing a match pass for £10.
Please note that subscribers based in the UK and Ireland will still need to purchase a match pass in order to watch the game live.
There will be post-match reaction on the website and our official YouTube channel, with highlights to follow on Wednesday.
Please note that current BBC guidelines mean commentators are not allowed to travel outside of their regions for games.
The BBC Radio Solent team will still be providing commentary from their studio, but there might be a slight delay between the pictures and the audio.
ALSO IN LEAGUE ONE
Games kick-off at 7pm unless stated
AFC Wimbledon v Gillingham (6.30pm)
Blackpool v Doncaster
Bristol Rovers v Wigan
Charlton v Burton
Crewe v Accrington
Hull v Ipswich
Lincoln v Swindon
Northampton v Rochdale
Shrewsbury v MK Dons
Sunderland v Fleetwood
Plymouth v Peterborough (7.30pm)