The defender, who joined the Red Devils from Villarreal earlier in the summer transfer window, was named man of the match as he put in an impressive displays for United in their opening weekend win over Bournemouth on Sunday afternoon.
Bailly started the game on the south coast with Chris Smalling missing, and Mourinho has admitted that he has been very encouraged by what he has seen from the Ivory Coast international since his arrival at the club.
Speaking to BT Sport after Sunday’s win over Bournemouth, Mourinho said: “Playing in Spain is different than England. Playing in Villarreal is different than Man United.
“Playing to finish four, five, six in the table is different to trying to win it.
“But he’s showing big personality, which is incredible.
“But I think to be surrounded by organisation makes life easier. And the team was very solid, very compact.
“So we create a habitat of stability. But the reality is that he’s showing great qualities.”
United won their first piece of silverware under Mourinho earlier this month as he guided them to Community Shield glory over Leicester City at Wembley.
The Portuguese coach is now preparing his side for their first Premier League home game of the season, when they host Southampton at Old Trafford on Friday night.
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