THE longer Celtic can keep the game goalless in Amsterdam on Wednesday, the more anxious Frank de Boer and his players - coming off the back of a home defeat - will become because the onus is very much on them to win.
There's no need for Celtic to go chasing the opener. The deeper into the match they can remain level, the more chances the Dutch will have to take. This will open the door for a swift and effective counter-attack.
A solid back four with deep-sitting cover directly in front in the form of Beram Kayal, Joe Ledley and Charlie Mulgrew will frustrate Ajax, who like to try and play through their opponents.
James Forrest or Georgios Samaras can provide the out ball, while Kris Commons or Anthony Stokes must look to shoot at any opportunity. This is a night when who comes off the bench might hold the key to success.
DISCIPLINE says ALISON McCONNELL:
With Georgios Samaras, James Forrest and Kris Commons all fit, it will be a relatively attacking formation Neil Lennon is able to put out.
With Samaras on the left-hand side, Stokes up front with Commons just behind him and Forrest on the opposite flank, Celtic will be capable of creating opportunities.
Taking them will be vital.
Ajax showed in Glasgow they are capable of keeping the ball, of being patient and it is expected that, for much of the night, Celtic may well be chasing shadows with the Dutch expected to see the bulk of possession.
If, as expected, it is Beram Kayal and Charlie Mulgrew in the middle, with Efe Ambrose and Virgil van Dijk at the heart of defence with Emilio Izaguirre and Mikael Lustig as full-backs, Celtic's discipline and shape will be key as they restrict the space that Frank de Boer's side have.
What they do without the ball will be just as important as what they do with it.