Mikel Arteta has expressed concern that his squad's pursuit for honors this campaign is being threatened by a worrying cycle of fitness setbacks and a grueling fixture list.
Star player Declan Rice did not travel for the Champions League clash to Belgium due to sickness. In addition, forward Leandro Trossard and defender William Saliba are still unavailable.
There was, on a brighter note, better news regarding Gabriel Jesus, with the South American forward added to their Champions League squad. He replaces the injured youngster Max Dowman, who picked up an ankle injury.
"Training, no because we don't have time to train. But obviously the fact that you are without players, you are loading other players more, there's a knock-on effect to that and it's a really dangerous circle."
Dowman's issue is the most recent in a long series of fitness problems for the North London side. Since the start of last campaign, they have recorded 95 player absences, the second-highest total in the English top flight.
Arteta dismissed the idea that practice methods were to blame, citing a lack of time for drills. He highlighted the pressure on fit players, some of whom have featured over 150 matches in two seasons.
Even after a major summer spend over £250 million, Arteta insisted the team is not looking to dip into the winter recruitment market.
"Right now we're just focusing on getting the players back and hopefully it will be a question of weeks," he said. "It's clear how important those coming weeks are going to be."
The team suffered their initial defeat in 18 matches at the hands of Aston Villa, cutting their advantage at the summit of the Premier League to two clear points.
Attention now turns to the European stage, where a sixth consecutive group win would virtually secure a top-eight place. Winger Gabriel Martinelli could make history by finding the net in a fifth successive Champions League fixture.
"The team is frustrated with the result, but we have to keep going," he stated. "This isn't like all is going badly because we lost one game. So we stick together."