The 25-year-old leaves a considerable gap in the middle of the pitch for the Saints after four seasons at the club and Ralph Hasenhuttl will look ahead to finding his replacement.
One of Schalke’s shining lights remains Weston McKennie in central midfield. The 21-year-old has already been capped 19 times by the United States, having arrived in Germany out of the FC Dallas academy in the summer of 2016.
He would be a like-for-like replacement for Hojbjerg in that he is a powerful runner between boxes and can affect a game on either side of the ball.
In a team that likes to press as Southampton does, McKennie would fit in perfectly with his tenacious tackling mixed with pace and fitness through the middle of the pitch.
The American is also willing to get further forward, shoot from outside of the box and make late runs to support forward players.
McKennie could be available with Schalke drifting well out of European places after a torrid end to the season, and at his age and with his skillset he could just be the ideal man to come in.
Abdoulaye Doucoure has asserted himself as one of the competitions leading defensive midfielders in previous years, but he does much more than just defend.
A tally of 17 goals and 11 assists in four seasons in his role is not to be scoffed at, with his mix of pace and power becoming a handful for defenders when at full tilt.
Doucoure became adept at playing off the likes of Troy Deeney and arriving late into the box to cause havoc, as well as having the legs and the strength to consistently win balls back for his team.
By no means a giant at 182cm tall, Doucoure wins a good percentage of aerial duels, is strong in the tackle and gets forward well. At 27 years of age, the Frenchman is yet to hit his prime and could be a fantastic addition at St. Mary’s.
Stuttgart’s Orel Mangala seems to be the frontrunner to move to the South Coast after helping his side to promotion back to the Bundesliga last season.
The 22-year-old is more of a ball-playing no.6, someone who enjoys getting on the ball in the middle of the pitch and relishes being the main pivot for his team.
The Belgian would allow for more flexibility in Hasenhuttl’s midfield ranks. He would arrive as a deep-lying technician, with Oriol Romeu remaining as a ball winner and allowing James Ward-Prowse to advance and link with the front players.
Stuttgart have a similar pressing philosophy to the Saints and Mangala would fit in well, both from a tactical sense and from a consistency point of view to get the best out of each of Southampton’s midfielders.
Having arrived last summer from Huddersfield, the 24-year-old played 34 times in the league and formed one of the more exciting midfield partnerships alongside Jefferson Lerma.
He stands at an incredible 196cm tall, but he uses that length so well by also picking up the right positions to win balls back and get his team going forward again.
Alongside that length, Billing also has an impressive mobility and is again adept at getting up and down the pitch for an entire 90 minutes.
Billing could be available on the cheap after the Cherries’ relegation, and he would be a great option to replace his compatriot Hojbjerg.
Hasenhuttl can actually replace his former skipper without having to part with any fee. He has loan players returning to the club and youth prospects ready to stamp their authority on the first-team.
Will Smallbone recently penned a new long-term deal at the club and looks to have a bright future at St. Mary’s. His intelligence between the lines and courage to go forward and play balls in behind add another dimension to Southampton’s creativity.
Harrison Reed has been there as a highly-rated talent coming out of the academy, but the last few seasons just haven’t quite materialised for him at the club.
The now 25-year-old has spent the last three seasons on loan in the Championship, this time playing for promoted Fulham. Next season could be a pivotal one for him if he is given a chance.
Mario Lemina is something of a forgotten man at Southampton, having spent 2019/20 on loan in Turkey with Galatasaray.
The Gabon international has proven quality and experience in big competitions, and could yet find himself with a role in Hasenhuttl’s team.