Arsenal's injury concerns ahead of their Champions League clash with Atletico Madrid have deepened, as Monday's open training session provided few reasons for optimism. The Gunners' medical team will be working overtime after none of the four key players sidelined with injuries were spotted taking part in the media-visible session.

Mikel Merino, Jurrien Timber, Kai Havertz, and Martin Odegaard were all notable absentees from the training ground, casting doubt on their availability for Tuesday's crucial fixture. While it's not uncommon for managers to hold back injured players for extra rest—especially in high-stakes European matches—the lack of any positive sighting is a worrying sign for Arsenal supporters hoping for a timely boost.

There was a silver lining, however, as Bukayo Saka was seen training with the first team. The winger's involvement confirms he has suffered no setback after being substituted at half-time against Fulham, providing some relief for manager Mikel Arteta.

To bolster numbers, academy prospects Marli Salmon and Josh Ogunnaike joined the senior squad in training, offering additional defensive cover. With Champions League benches now expanded, both youngsters could find themselves in contention for a spot in the matchday squad. Salmon and third-choice goalkeeper Tommy Setford were already on the bench for the first leg in Madrid, even before Odegaard's injury.

Despite the injury woes, Arsenal should still be able to field a similar lineup to the one that started in Madrid or against Fulham. Odegaard remains the only current doubt among the starters from those matches. As for Havertz, Timber, and Merino, their absence has been a recurring theme over the past week, so Tuesday's game may simply be more of the same for the Gunners.