By 1970's Gooner
All the Arsenal players on World Cup duty seem to have returned to London Colney. Those who were knocked out in the earlier rounds of the tournament have already been assimilated back into the squad and are getting valuable training time preparing for the West Ham game. These are White, Ramsdale, Xhaka, Saka and Turner (the latter two had a very good World Cup), Partey and Martinelli.
The exceptions have been of course Jesus with his well known injury problem and Tomiyasu who seems to have been carrying an injury. The latter has not featured in any of the friendly games and will be doubtful for the West Ham game. In any case Ben white will start at the right back position on Monday.
The only remaining player is Saliba who was part of the France squad but did not get any time. If he takes the week off after the World Cup final, as he is entitled to do, then he will only have had a day with the team and will most probably be out of the West Ham game.
But even if he did return right after the end of the World Cup then he will only have had a week's training with the team. Taking into consideration that he didn't play at all during the tournament then one week of training will probably not be enough to get him up to match fitness.
Which leads me to conclude that Rob Holding will be starting on Boxing Day as he has been training all throughout the time the others were at the World Cup and played in all of the friendly games in Dubai and at the Emitates.
Saliba may be on the bench.
The other position that Arteta will need to decide is the left back. Zinchenko has been carrying an injury and even if he shakes it off he has not been able to train much but more importantly he has not played in any of the friendlies. Tierney has and looks fit and ready to go.
White Holding Gabriel Tierney
Saka Nketiah Martinelli