The Chile international has been out of action since late November due to a hamstring injury but could make his return when the Gunners host the Blues at Emirates Stadium this weekend.
Sanchez was put through his paces along with the rest of his Arsenal team-mates as they prepare to welcome the champions to their home ground.
Midfielder Francis Coquelin was also pictured in action, although the Frenchman is unlikely to feature against Chelsea this weekend following his lay-off with a knee injury.
Arsenal head into the game top of the table on goal difference.
Here are some of the best pictures from Saturday’s Arsenal training session ahead of their game with Chelsea.
MORE: The latest football news