Arsenal could be without Theo Walcott when they take on Schalke with their UEFA Champions League participation in doubt.
If the Gunners lose to Schalke in Germany on Tuesday evening, then Arsene Wenger's side could be on the brink of elimination from the Champions League group stages for the first time in 13 campaigns.
Defeat by the Bundesliga club at Emirates Stadium on Matchday Three saw the Gunners surrender a 45-game unbeaten streak at home to continental opposition and leaves them second in Group B.
Arsenal only trail Schalke by one point but are also just three points ahead of third-placed Olympiakos, who host Montpellier, and it could be set for a tense conclusion to the group.
That is the last thing Wenger, who has now completed the final match of his three-game touchline ban in Europe, needs at a time when his club are under mass scrutiny.
Defeats by Norwich City and Manchester United as well as a much-publicised AGM have surrounded the loss to Schalke and the dramatic 7-5 Capital One Cup win over Reading only really papered over the cracks.
Another setback in the shape of a loss to Huub Stevens' side in Gelsenkirchen would therefore put an immense amount of pressure on Wenger.