Manchester United have made contact with Royal Antwerp over a deal for goalkeeper Senne Lammens, sources have told ESPN.
United are not looking to replace current No.1 André Onana, according to sources, but are interested in boosting their group of goalkeepers with the former Belgium under-21 international.
Antwerp value Lammens at around €20 million ($23.4m).
Should the 23-year-old arrive at Old Trafford, sources have told ESPN it would raise questions about the future of Altay Bayindir.
Bayindir, Onana's understudy, was at fault for Arsenal's winner in United's 1-0 defeat to Mikel Arteta's side on the opening weekend of the Premier League season.
Onana, who missed United's preseason schedule with a hamstring injury, is fit to make his return against Fulham at Craven Cottage on Sunday.
United, according to sources, are expecting the Cameroon international to remain at the club beyond the transfer deadline.
Senior sources at Old Trafford have firmly denied interest in signing Gianluigi Donnarumma, who is surplus to requirements at Paris Saint-Germain.
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Donnarumma has also been linked with a move to Manchester City if Éderson joins Galatasaray.
The Turkish side are looking to sign a goalkeeper before the deadline and have narrowed their search to a three-man short-list of Ederson, Diogo Costa and Yann Sommer.