I'm curious about how determined Arsenal will be for the Europa League title. So far they have done a great job about balancing the English Premier League and Europa League. They have performed strongly in both of the tournaments. There will be a long break for the rest of the games to start now.
Unless they have to deal with serious injuries after the World Cup ends, I don't expect Arsenal to lose their concentration and start struggling in any of these tournaments. Besides they might add new players to their squad in January as well which would help them a lot in the rest of the season.
There are 10 Arsenal players who will play in the World Cup and it is difficult to avoid players experiencing injuries in the World Cup, especially if these players are core players who get a lot of playing portions in the national team and this can be detrimental for Arsenal and disrupt what has been built so far, and maybe will be able to change their focus which competition will be the main target.
However, this is not only a worry for Arsenal but many football clubs whose players have to play in the World Cup, which is why this World Cup has received quite a lot of criticism because the schedule which is held in the middle of the season for the big leagues will make players injured and suffer fatigue.