The Red Devils are thought to be interested in a move to sign the 23-year-old as a potential alternative to Tottenham Hotspur centre-half Toby Alderweireld.
Mina, who moved to FC Barcelona from Brazilian side Palmeiras, rose to prominence during the World Cup as he helped the Colombia to reach the round of 16.
He registered on the radar of Premier League supporters after his goal forced extra time in Colombia’s 1-1 draw with England before Gareth Southgate’s men won on penalties.
Mina has made a mere six appearances for FC Barcelona since his move in the January transfer window but the Catalan side could make a tidy profit on the €11.8m transfer fee.
Sunday Times reporter Castles confirmed that Manchester United have been scouting Mina for some time.
“Mina is an alternative,” Castles told the Transfer Window podcast.
“He is a high quality player. They have scouted him for a long time. He could potentially be the best of those players. He is 23. He is physical. He is an obvious fit for how Mourinho likes to play. However there is a question of adaption.”
Manchester United have signed three players in the summer transfer window following their second-placed finish under Mourinho last term.
The Red Devils snapped up FC Porto full-back Diogo Dalot, Shakhtar Donetsk midfielder Fred and Stoke City veteran goalkeeper Lee Grant in the summer transfer window.
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