While attention focuses on the players Celtic hope to sign, a far more alarming question is beginning to emerge.
Who will actually be left in midfield?
The speculation surrounding Arne Engels and Reo Hatate refuses to disappear. There are also questions around Callum McGregor, Benjamin Nygren and Paulo Bernardo.
One potential departure would be manageable. Losing several of them in the same window could decimate Celtic’s midfield.
Celtic could lose the heart of the team
Midfield is the engine room of any successful side.
It controls possession, dictates the tempo, protects the defence and creates opportunities for the forwards.
Take away too many components at once and the entire machine begins to splutter.
If Engels and Hatate leave, Celtic lose creativity, energy and technical quality. If uncertainty around McGregor, Nygren or Bernardo becomes something more serious, the options could disappear at a frightening rate.
Celtic could then be left relying heavily on Luke McCowan and Alex Oxlade-Chamberlain.
Both could have important roles. However, asking them to carry a midfield built to compete domestically and in Europe would represent an enormous gamble.
Where is the succession planning?
This situation should not be developing so close to the new season.
Well-run clubs understand that valuable players may leave. They prepare replacements before accepting offers.
Celtic too often appear to begin planning only after the removal van has left the training ground.
The club should already have a list of midfield targets ready. Ideally, replacements should arrive before key players depart, allowing them time to settle into Martin O’Neill’s system.
Instead, supporters face the possibility of another frantic final stretch of the transfer window.
That is not strategic planning. It is football administration by fire alarm.
New forwards will not solve everything
The possible arrivals of Kasper Høgh, Haissem Hassan and Mika Baur would give Celtic a welcome lift.
However, strengthening the attack while allowing the midfield to be dismantled would make little sense.
A quality striker cannot score without service. A winger cannot attack consistently if the team cannot control possession. A defence will struggle if the midfield in front of it offers inadequate protection.
Champions League football punishes weak planning. Opponents at that level expose every gap, every imbalance and every shortage of quality.
Celtic cannot enter Europe with a midfield patched together after several late departures.
Celtic must act before the damage is done
The board cannot claim to have been surprised if these players leave.
The speculation has existed for long enough. Celtic should be prepared for every realistic scenario.
Supporters will welcome ambitious attacking additions, but the midfield now requires urgent attention.
Failure to protect the heart of the team could undermine every positive deal completed elsewhere.
The warning signs are already flashing.
Celtic must act before a concern becomes a crisis and the feared midfield decimation becomes reality.