Arsenal duo Martin Zubimendi and Piero Hincapie were both absent from open training on Monday morning following reported injury blows for the pair.
The Gunners return to Champions League action on Tuesday night when they welcome Lille to the Emirates Stadium, aiming to go two for two after edging out Napoli 1-0 last month.
Mikel Arteta is expected to make a number of changes to his starting XI given the tight turnaround from Saturday's 2-1 Premier League win over Leeds United, which Zubimendi and Hincapie were both substitutes for.
However, the pair were both said to have suffered injuries in the warm-down, Hincapie sustaining an ankle problem that required the defender to be carried off the pitch by Illan Meslier.
Shortly after the worrying Hincapie footage was released, reports emerged claiming that Zubimendi had picked up a knock in the warm-down, and both blows have now seemingly been confirmed.
Piero Hincapie, Martin Zubimendi missing from Arsenal training before Lille
Arsenal out for open training pre-Lille No sign of Hincapie or Zubimendi https://t.co/vfgjgEuehp
— Art de Roché (@ArtdeRoche) October 12, 2026
As is customary before European games, Arsenal opened up the first part of their training session to the media on Monday morning, and neither Hincapie nor Zubimendi were alongside their teammates at London Colney.
Arteta will likely be asked for an update on both players when he conducts his pre-game press conference, but the pair are now extremely unlikely to be ready for the visit of Les Dogues on Tuesday.
Hincapie and Zubimendi were two of four Arsenal players absent from the Monday morning team training session, as Christos Tzolis (hamstring) and William Saliba (back) were also missing as expected.
Tzolis has been ruled out for a few weeks with the hamstring injury he picked up during the international break, while Saliba is not expected to return from his serious back problem for a few weeks.
Saliba supposedly took part in individual training on the grass, though, suggesting that the centre-back's recovery is on track.
However, every other senior Arsenal player was seen in training, including Cristhian Mosquera, who was the 12th man against Leeds after recovering from a hamstring concern of his own.
How Arsenal could line up against Lille after double injury blow
Hincapie and Zubimendi should have both been in contention to start against Lille in the Champions League, having both been second-string players in the current Premier League season so far.
Hincapie played the full 90 against Napoli, but Arteta will now have no choice but to persist with Riccardo Calafiori at left-back, or move Myles Lewis-Skelly out of midfield if he wishes to grant the Italian a rest.
Zubimendi was snubbed from the starting lineup in Naples, though, as Arteta selected Mikel Merino to partner Declan Rice; Zubimendi was only an 82nd minute substitute for Ben White.
Rice played the full 90 against Leeds after withdrawing from the England squad, so Merino and Bruno Guimaraes now appears the most likely midfield pairing for Tuesday's game if Zubimendi is indeed ruled out.
Viktor Gyokeres and Eberechi Eze have also been tipped to start for Arsenal against Lille, while Max Dowman and Marli Salmon - who also trained with the first team on Monday - could earn valuable European minutes off the bench.