Eddie Howe’s side were originally due to face the Saints on January 2 but the game was postponed following a Covid-19 outbreak in United’s camp.
The Magpies also had a long list of injuries but Ralph Hasenhuttl voiced his frustration at the match being cancelled.
In his comments at the beginning of the year, Hasenhuttl insisted players signed by Newcastle in January should not be allowed to play in the re-arranged fixture.
The Saints boss said: “We were discussing in the last Premier League meeting about what happens with the winter signings for the postponed games, if they’re allowed to play or not.
“For us it’s the same, we can now also with our new owners sign new players and that is not really fair to play in games that have been postponed.
“The last word has not been spoken so far.”
Had Hasenhuttl’s theory come into play, that would have United left without Chris Wood, Bruno Guimaraes, Matt Targett and Dan Burn for the visit to St Mary’s.
We take a look at how Newcastle could have lined up against Southampton had the Austrian got his way: