Sources say Mauk is likely to leave the Reds to take up an opportunity to play in Japan.

InDaily understands Adelaide offered Mauk one of the most lucrative contracts in the club’s history, however Mauk’s Japanese offer exceeds it, and insiders say he has advised the Reds he wants to have another crack overseas.

InDaily has sought comment from Adelaide United and Mauk’s agent Vince Grella, but has not received a response.

However, it’s understood that with his contract expiring at the end of the current season, the Reds have agreed to let Mauk leave now so they can get a transfer fee for the 26-year-old instead of losing him for nothing at the end of the season.

Website TransferMarkt currently lists Mauk’s value at just under $1.2 million, but it’s very unlikely United will get anywhere near that value.

It would be the second time that United have cashed in on Mauk, previously selling him to Dutch club NEC Nijmegen after the title winning campaign in 2016.

There is however a slim chance that the deal won’t proceed if Mauk’s visa is not approved.

The South Australian has been a solid contributor since re-joining the Reds after a stint with Brisbane Roar.

He became Adelaide’s captain at the start of last season and was ever present for United, scoring seven goals in the league despite playing most of the season with a broken leg.

Losing Mauk would be another blow to the Reds, who announced the departure of Ben Halloran to the K-League on Saturday.

Adelaide have relied heavily on Mauk playing as their 10, despite it not being his preferred midfield role.

His pending departure means Adelaide could recruit a natural 10, something they themselves identified as a priority in the pre-season.

So far United has signed local players to fill the voids created by the departure of Al Hassan Toure and the season ending injury to Nick Ansell (namely Asad Kasumovic and Lachlan Barr).

The club is currently trialling midfielder-cum-striker Nahuel Bonada. Bonada, an Argentinian, has been very good at NPL level for the last few years in South Australia and Victoria. But, without any experience at senior level (apart from a six-week trial at Central Coast Mariners which did not eventuate in a contract) it may take Bonada time to adjust to senior level.

If United do not replace Mauk, it would need Carl Veart and Ross Aloisi to again plug the important 10 role with someone who’s not a natural in that position. The most logical option was Ben Halloran, but that is no longer possible.

Alternatively, the coaching staff may decide to take on a new tactical approach which would not require the team to utilise a 10.

With Halloran gone, Mauk going and Kusini Yengi on the long-term injury list, it again raises questions around the decision to allow Al Hassan Toure to depart for Macarthur.

At the time he was released, the club cited Toure’s want to play as a winger as the reason they allowed him to pursue a deal with Macarthur. They also suggested they didn’t want to stall Toure’s progress by denying him the regular game-time he needed to develop.

The decision to allow Al Hassan to walk for nothing to an A-League rival, irrespective of the reasons, seems even more short sighted now than it did when it occurred.

The Reds will also need to appoint a new leader.

Adelaide’s previous two captains, Jakobsen and Isaias, are at the club and either could assume the role again.

Another option could be Craig Goodwin but as he is only on loan, and with no certainty he would stay with Adelaide beyond this season, United may not choose to go down that path.

The Reds play fierce rivals Melbourne Victory tomorrow night in an FFA Cup Quarter Final. Both teams are expected to field rotated teams for the match. Adelaide could use the game to get minutes into the legs of players like Timotheou, D’Arrigo, Dukuly, Caletti, Popovic, Barr (assuming he’s not cup tied), Kasumovic (who’s also potentially cup tied) and Yull.

16-year-old goalkeeper Steven Hall, who was thrust into the spotlight when James Delianov got injured against Wellington, will continue between the posts for United, with either Joe Gauci or Ethan Cox on the bench.