Marcos Rojo is set to play an hour for Manchester United's reserve team on Thursday as Louis van Gaal tries to get the defender back to first-team football.
Rojo has not played since representing Argentina in their Copa America final defeat to Chile on July 4.
He was then granted time off and was supposed to join up with his club's preseason tour of the United States, only to have visa issues.
The former Sporting Lisbon player has not even been on the bench for United's first four competitive games and Van Gaal has not taken him to Belgium for Wednesday's Champions League qualifier against Club Brugge.
Along with many of United's other squad members, who have not had much first-team football as the manager has only given 13 players a start so far, he is set to face Ajax in a friendly later this week.
Van Gaal believes players need to get "match rhythm" before featuring for the senior side and said in a news conference: "The only way is to play matches in the second team because that is the first step to come back.
"So now seven or eight players have to play against a young Ajax second team on Thursday because they need also to play 90 minutes and Rojo shall play 60 minutes."
The United manager did not reveal if David De Gea, who he has not picked because of concerns about his state of mind while talk of a move to Real Madrid persists, in the midweek game.
However, he said the lack of second-team games scheduled in the opening weeks of the season "is a great problem."
United began their Under-21 Premier League fixtures against Leicester on Aug. 10, when they drew 1-1, but they do not have another game scheduled until Sept. 13, when they visit Chelsea.
Van Gaal was unsure why there was a five-week gap in competitive games, saying: "I don't know. You have to ask the federation."