The 20-year-old attacking midfielder got on the scoresheet in a 3-1 away defeat against Sampdoria, and impressed in an otherwise under-par team performance at Stadio Luigi Ferraris.
Mancini is reportedly keen to revamp his attacking options at the Etihad Stadium, having fallen 12-points off the pace of leaders Manchester United, as they bid to retain their Premier League title.
Summer signing Scott Sinclair has made little, to no impact whatsoever since joining Manchester City from Swansea, while Samir Nasri's form has also suffered in 2012/13.
The Italian tactician is ready to sell both players, and believes Lamela could thrive alongside David Silva, and fellow South American's Sergio Aguero and Carlos Tevez in England.
Lamela joined Roma for an initial £15million in 2011, and has notched 11 goals and two assists in Serie 'A' this season. However, despite his impressive form, the Italian giants could be open to selling the former River Plate star, as long as the price is right.