Manchester United manager Erik ten Hag admits Sofyan Amrabat took time to settle in midweek.
The Moroccan had to play at left-back for the Red Devils in an FA Cup game against Nottingham Forest.
United secured the result through a last minute Casemiro winner from a Bruno Fernandes free-kick.
After the narrow 1-0 win that secured United's spot in the quarter finals, Ten Hag praised Amrabat for his adaptability.
He told club media: “For Sofyan, he is not a full-back, but he played a solid game, especially I think after 55 minutes when he played in the middle [when we were] in possession.
“Then also, he understood what to do in the defending, in the rest defence, and from that moment on we took the control."