Roma are pursuing a deal for Manchester United defender Chris Smalling in the final days of the transfer window, sources have told ESPN FC.

The Serie A side are one of a number of clubs to have expressed an interest in a loan deal for Smalling, who has been left out of the matchday squad in each of United's three games this season.

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Valencia, Inter Milan and Juventus have also made enquiries about signing Matteo Darmian before the European transfer deadline on Monday.

The Italy full-back is also yet to feature this season and has entered the final year of his contract at Old Trafford.

Smalling was at Carrington on Thursday morning as United continued their preparations for the visit to Southampton on Saturday.

The centre-back, who signed a new long-term contact last season, has slipped down the pecking order after the arrival of Harry Maguire from Leicester in the summer.

Manager Ole Gunnar Solskjaer has paired Maguire with Victor Lindelof and picked youngster Axel Tuanzebe on the bench as cover leaving Smalling in the cold.

United knocked back a loan bid from Smalling from Everton ahead of the Premier League deadline.

Roma had been in the market for a new defender with Dejan Lovren and Daniele Rugani among their main targets, but have opted for Smalling instead.

Smalling, 29, joined United from Fulham in 2010 and has won two Premier League titles, the FA Cup, League Cup and Europa League.

He was also named the club's Players' Player of the Year for 2015-16.