Manchester United reportedly deem Diogo Dalot to be 'untouchable' at the club due to his form during the 2021-22 campaign.
The Portugal international was strongly linked with a move away from Old Trafford last summer, with AC Milan said to be keen to sign the right-back on a permanent basis.
Dalot remained with the Red Devils, though, and he has been an important player this season, making 16 appearances in all competitions, including 12 outings in the Premier League.
According to Italian journalist Fabrizio Romano, Borussia Dortmund wanted to sign the right-back last summer and were planning to make another move in January.
However, Romano claims that there is now zero chance of the Portuguese being allowed to leave Ralf Rangnick's side due to his recent development.
The 22-year-old, who has entered the final 18 months of his contract at Old Trafford, has started seven of Man United's last nine Premier League matches.