article_snippet.sent: Mertesacker pictured during a training session with Mertesacker Arsenal team-mates on Friday ahead of the clash .
article_snippet.sent: Alexis Sanchez looked in good spirits as Alexis Sanchez cheered on Alexis Sanchez team-mates during his team-mates training session .
article_snippet.sent: Calum Chambers reacts as Danny Welbeck laughs during training as they prepare to defend they the FA Cup win .
article_snippet.sent: Mesut Ozil and Mathieu Flamini acknowledge each other during the Arsenal training session on Friday . '
article_snippet.sent: Chambers and Ozil during training in London on Friday morning ahead of Saturday's semi-final .