Anthony Martial and Jadon Sancho were among the Manchester United players to return for the first official day of pre-season training.
Tom Heaton, Aaron Wan-Bissaka, Raphael Varane and Fred also arrived at United's Carrington training complex on Thursday morning.
Amad and Hannibal Mejbri were back at United after season-long loans in the Championship with Sunderland and Birmingham City.
Amad, 20, excelled at the Stadium of Light, scoring 14 goals in 42 appearances as Sunderland reached the play-offs. United manager Erik ten Hag indicated in May that Amad would stay in the squad for the forthcoming season. Also read: United open to signing two goalkeepers Mejbri, also 20, faces an uncertain future at United and Borussia Dortmund are interested in the Tunisia international.