The Ivory Coast international, currently representing his country at the Africa Cup of Nations, had already made the breakthrough at Atalanta in Serie A but the signing was viewed as a gamble.
However, our no.16 developed during loan spells away from the club at Rangers and by proving his quality with Sunderland, and returned ready to compete for a spot in the first team.
He had to bide his time but took his opportunities and has become a firm favourite with the Old Trafford faithful.
"My first day at the club, I was happy, but I was emotional to sign for this club because I wanted to play for Manchester United," he told us, when looking back on his arrival here, after the transfer was delayed until January to allow for the opening of the winter window.