The 31-year-old returned to his boyhood club Everton one year before the expiration of his contract at Old Trafford.
Rooney slipped down the pecking order under manager Jose Mourinho last season, but he still managed to make history by becoming the club's record scorer with 253 goals to his name.
Despite the forward moving to Goodison Park, the club intend to offer him a role that will see him travel the world promoting United when he decides to hang up his boots, according to The Mirror.
The role was promised in the contract that Rooney signed in 2014, and even though it is no longer valid now that he is left the club, the offer reportedly still stands.
The England international won 12 trophies, including five Premier League titles, during his 13-year spell at Old Trafford.