The Red Devils have been heavily linked with a big-money swoop for the Spain international defender as Louis van Gaal looks to bolster his rearguard ahead of his second season in charge at the club.
And former Real Madrid assistant Clement feels that Ramos is up there with the very best centre-halves in the world.
Clement told Sky Sports: “He is a wonderful player, one of the best I have ever worked with.
“So many qualities, a fantastic footballer, leader, competitor, athlete, a fantastic guy.
“He is one of the best centre-halves in the world and I’ve worked with some good ones like John Terry, Thiago Silva at PSG, good ones in Pepe and Raphael Varane but Ramos is up there with the best I’ve worked with.
“Whether at Real Madrid or United, either club are going to massively benefit.
“Wherever he is, it’s going to a massive plus for that club.”
It has been suggested that Ramos could be included as part of the deal which sees David De Gea secure a move to the Bernabeu.
Ramos has won three La Liga titles, three Copa del Rey crowns and the Champions League with Real Madrid.
The Real Madrid defender is set to become a free agent in the summer of 2017 unless the World Cup winner agrees a new deal with the 10-time European champions.
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