Arsene Wenger’s men were put through their paces at a cold and grey London Colney ahead of their lunchtime visit to The Hawthorns in the Premier League.
Midfielder Mikel Arteta has been ruled out of the game after suffering a fresh calf injury during the 2-0 Champions League win over Borussia Dortmund in midweek.
Theo Walcott is also out due to the groin problem he picked up while on international duty with England.
However, centre-half Laurent Koscielny is fit and ready to return to action – and the France international was pictured taking part in Friday’s training session at London Colney.
Here are some of the best pictures from Friday morning’s session.
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