The Chile international was put through his paces along with the rest of Arsene Wenger’s squad on Saturday morning ahead of their third league game of the campaign.
Sánchez, 25, is expected to lead the Arsenal attack in the absence of first-choice striker Olivier Giroud, who has been ruled out of action until the new year due to a broken leg.
The former Barcelona man scored his first goal for his new club on Wednesday as he helped Wenger’s men book their place in the group stage of the Champions League with victory over Besiktas.
The Gunners will be able to call upon midfielder Aaron Ramsey once again after he missed the midweek game through suspension, but Kieran Gibbs and Mikel Arteta remain sidelined.
Arsenal have four points from their opening two games after victory over Crystal Palace and last weekend’s draw at Everton.
Here are some of the best pictures from Saturday’s training session at London Colney.
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