The timing of the sale of Arne Engels remains a head-scratching one for those of a Celtic persuasion, with that decision coming home to roost away in Linz.

Having waited until mid-August to cash in anyway, couldn't the Parkhead hierarchy have strung West Ham United along just a little longer, to ensure the Belgian was available to feature in that pivotal Champions League tie?

As it is, the Scottish champions paid the price following that dismal collapse against LASK, with even the £22m fee raked in for Engels not exactly aiding matters amid the lack of a succession plan.

As the weekend defeat to Rangers showcased, the void left behind by the 23-year-old is yet to be filled.

Why midfield remains Celtic's biggest issue right now

Celtic's upturn in form at the end of last season notably coincided with Engels' return from injury, with Martin O'Neill having struggled to settle on a consistent partner for Callum McGregor.

The £11m signing had his critics, but he had notably started the new campaign in fine fettle, looking like a true powerhouse in the thumping 5-1 win away at Kilmarnock.

Alas, his much-needed athleticism, mobility and creativity are now sorely missed, with the trip to Ibrox illustrating that in the biggest games, a trio of McGregor, Benjamin Nygren and Mika Baur just doesn't cut it.

It was that same trio that started proceedings in Austria too, with the Hoops simply getting overrun on both occasions. Indeed, Dan Neil had a field day on Sunday afternoon.

McGregor remains central to this team and this club, while the diminutive Baur has his merits as a technical, ball-playing talent, but it really should be a case of one or the other, particularly if Nygren is deployed ahead of them.

With Ferencvaros on the agenda in the Europa League on Thursday night, O'Neill will surely have learned lessons from these recent outings, with the 74-year-old needing to find a way to try and bring a sense of balance back to that midfield unit.

Thankfully, the perfect replacement for Engels might already be in the building at Parkhead.

Why Celtic's new Engels has to start against Ferencvaros

There is depth in O'Neill's midfield department, but is there genuine quality? That still needs to be decided.

Luke McCowan, the man likely to challenge Nygren in that number ten role, was abject against LASK, having surely plummeted down the pecking order.

As for Alex Oxlade-Chamberlain, the veteran Englishman will again be absent this evening due to suspension, while teenage arrival, Joel van den Berg, has been left out of the Europa League squad altogether.

That leaves fellow summer signing, Oliver Sorensen, as the only clear option to replace one of Baur, McGregor or Nygren against the Hungarian outfit, with the Dane arguably the closest thing Celtic have to Engels right now.

Of course, it's been a muted start to life in Glasgow for the 24-year-old, with Sorensen looking particularly anonymous in the narrow win against St Johnstone last week.

That forgettable outing had come with the on-loan Parma star lining up in an ill-suited advanced midfield role, however, with that seemingly not the best use of his talents.

The left-footer, at 6 foot 2, has the engine and the physicality to flourish in a box-to-box berth instead, mirroring Engels as someone who can chip in too in terms of goals and assists.

His time in Serie A was underwhelming last season, although by his own admission, Sorensen struggled in a team fighting for relegation, having previously flourished in a front-footed FC Midtjylland side before that.

Indeed, in 2024/25, for instance, he scored nine and assisted three in the Danish Superliga, having created six 'big chances', while averaging 1.1 key passes per game.

Out of possession too, the Scandinavian averaged 1.7 tackles and interceptions per game, as well as 4.3 ball recoveries per outing, putting out fires all over the pitch. That was evident in the Europa League that season too, as he averaged 2.7 tackles per game from his seven appearances in the competition.

For context, that same season saw Engels enjoy a similar return of nine goals and six assists in the Premiership, albeit with the Belgian just behind in terms of tackles and interceptions (0.8) and ball recoveries (2.4).

Sorensen has also been given the backing of his fellow Dane, Erik Sviatchenko too, the former Celtic defender lauding his compatriot's physical qualities, as well as likening him to Kieran Tierney in terms of his "desire and hunger".

That's high praise indeed, and while Sorensen hasn't exactly made any sort of impression as yet in green and white, what better time to prove he is the next Engels in the making, amid what is a pivotal week for O'Neill and co.