The defensive midfielder is now club captain, and Flores believes that he is one of the senior members of the dressing room that others look up to.
The two have a history, with Sanchez Flores coaching Capoue the last time that he was at Watford as manager.
"He's really mature now," said the head coach to reporters about Capoue.
"Three years ago he was an amazing player, a very good player and very important for us.
"Three years later, he's the captain right now, also he's more mature, he's able to take and to organise some of the players - for us he's a very important player."