The Premier League champions tried to sign the Spaniard in 2010 when Sporting Director Brian Marwood attempted to lure Busquets away from the Nou Camp with no success. Reports suggest that Manchester City have now re-ignited their interest in the player.
Busquets is apparently unhappy at the arrival of Alex Song from Arsenal in the summer as a contender for his position as the defensive element in the Barcelona midfield.
So far this season, Song is being used as a centre-back by Barcelona boss Tito Villanova with Busquets making eleven appearances, which would suggest that the player has not been marginalised by the new signing.
However, Mancini is intent on signing a new star to improve his squad and the Italian believes Busquets and former team mate Yaya Toure would make an excellent partnership in the City midfield.
This summer, the Citizens signed Javi Garcia and Jack Rodwell, however neither have yet proved that they have the ability to play at the same level as Busquets, who plays an important role for a Barcelona team that have won many accolades.
The Spaniard is also a Catalan and has made 234 apperances for his beloved club. Barcelona have insisted the player is not for sale, and may offer the 24-year-old a new deal to end speculation regarding a move to the English top flight.
Should Mancini seriously want to sign the defensive midfielder, the club would have to offer a huge fee combined with a lucrative contract deal to convince the player to leave.