Former Manchester United youngster Demetri Mitchell is training with Sunderland as the Black Cats consider a move for the left-back.
Mitchell is one of several options being looked at by Phil Parkinson in that position, with Sunderland also understood to have offered a contract to ex-Everton defender Luke Garbutt.
The 23-year-old,who has represented England at U16, U17, U18, and U20 levels, is a free agent after leaving the Red Devils this summer.
He came through the youth system at Old Trafford and was named the club's reserve player of the year in 2018.
But he made only one senior appearance for the club, becoming one of four players given their first top flight starts by Jose Mourinho - in what was the youngest Man U line-up in Premier League history - on the final day of the 2016-2017 season, in a 2-0 home win over Crystal Palace.
Mitchell spent two loan spells with Scottish Premiership side Hearts, the first from January until June 2018 and the second from August 2018 until March 2019, where he made a total of 34 appearances in all competitions, and scored two goals.
Mitchell suffered a recurrence of a knee injury in his second loan spell with Hearts, and his recovery stretched into last season.
But he is now fully fit and is understood to have impressed in his time on Wearside.
Parkinson is looking for competition and cover for Denver Hume in the left wingback role and Mitchell would fit the bill.
Garbutt, who is also a free agent after leaving Everton this summer, is another possibility.
