Bayern Munich defender Jerome Boateng (aged 29), Raphael Varane of Real Madrid (25) and Kalidou Koulibaly of Napoli (27) were all options too.
In fact, Koulibaly was one of three Serie A defenders on the nine-man list. It also included AC Milan’s Alessio Romagnoli, a 23-year-old Italian rated as one of the best young defenders on the planet, and Inter Milan’s Milan Skriniar, also 23, from Slovakia.
Jose Gimenez of Atletico Madrid and Freiburg’s Caglar Soyuncu, a Turkish international, were also among the options.
Boss Mourinho has five centre-backs on the United books – Eric Bailly, Chris Smalling, Phil Jones, Victor Lindelof and Marcos Rojo – but he is said to have doubts over all of them.