Five of Arsenal's key players were missing from the open part of training before the Gunners quarter-final second-leg match against Sporting in the Champions League.
Arsenal have a 1-0 advantage from the first leg but have a number of injury issues in the squad.
Declan Rice, who played 90 minutes of Arsenal's 2-1 defeat to Bournemouth at the weekend, was not seen in the first 15 minutes of the training session that was open to the media.
Captain Martin Odegaard missed the game as did Bukayo Saka, Jurrien Timber and Riccardo Calafiori – all with injury issues.
This is a pivotal week for Arsenal in the season with the chance to reach the last four of the Champions League before a huge match against title rivals Manchester City on Sunday.
