Manchester United defender Chris Smalling has suffered an injury in Roma training and could be forced to wait for his Serie A debut.

The defender, who joined the Italian club on loan from Manchester United on September 1, pulled up with a muscle problem.

Smalling could have been set to make his bow at home to Sassuolo on Sunday, but will now undergo a scan to confirm his availability.

The 29-year-old departed Manchester United after nine seasons and 323 appearances for the club.

Roma are already without the likes of Leonardo Spinazzola, Davide Zappacosta, Diego Perotti and Cengiz Under through injury.