Gabriel, who recently returned from hamstring surgery, was given a break by Arteta and the medical team to allow him to continue his recovery, despite having played in a closed-door friendly.
Timber, who underwent surgery late in the 2024/25 season, is still in the process of rehabilitating and was not included in the matchday squad as he works towards full fitness.
Arteta explained that Timber is not yet fully trained with the team, and Gabriel had a minor issue in training, which led to the decision to manage their returns carefully.
He noted that the team's recent travels and changes in conditions have increased the risk of injury, and therefore, they need to take a cautious approach with players who have been out for a while.