Moyes did not attend his post-match press conference after the Black Cats’ 1-0 EFL Cup second round victory over Shrewsbury at the Stadium of Light, which booked them a third round trip to QPR, after the Atletico Madrid defender arrived on Wearside.
Assistant manager Paul Bracewell said: “The lad [Manquillo] is obviously having his medical at the moment. He came in this afternoon and he’s having his medical as we speak.”
A successful conclusion to that transfer – which is expected to be a season-long loan deal – would come as a fresh boost to Moyes, who saw his team win a competitive game for the first time since he took charge courtesy of Adnan Januzaj’s 83rd-minute strike.
Substitute George Waring might have taken the tie into extra time with an injury-time header, but missed the target from just three yards to leave Manchester United loanee Januzaj hanging on to the headlines.
Bracewell said: “That’s one of the reasons why the boss brought him in. All of a sudden, he can turn, and it was a great finish to get a result on a tough night.
“It’s a work in progress. Some things we were happy with and some things we weren’t. He’s got that ability to deliver something very special like that.
“We had a young team out tonight, one or two lads playing out of position as well. It was a tough game, but all in all the most important thing in the cup games is getting through.”