Man Utd defender Matthijs de Ligt involved in part of Monday's training session

The Netherlands international joined his teammates for the opening 15 minutes of Monday's session at the club's County Kildare training camp, before switching to an individual programme as he continues his rehabilitation.

De Ligt, 26, has been sidelined for more than eight months and has not featured for United since November.

His initial back injury was initially viewed as relatively minor, with a possible return in January or February mooted. However, repeated setbacks during the second half of the campaign eventually resulted in the centre-back undergoing surgery in May.

United have already confirmed that the 42.7-million-pound signing will not be ready for the beginning of the new season.

His latest involvement nevertheless represents encouraging progress, although it could still be several weeks before he is able to resume full training with the squad. He may also be eased back into competitive action through cameo appearances.

De Ligt enjoyed an impressive start to last season under former boss Ruben Amorim and was considered among United's better performers before his injury troubles. A full return would therefore provide manager Michael Carrick with a significant boost.

United currently have only Harry Maguire, Leny Yoro and Ayden Heaven as fit senior centre-backs. Lisandro Martinez is also recovering from an injury sustained during Argentina's World Cup final against Spain, although United's medical team expect him to be fit for the league opener away to Hull City. 

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