The 22-year-old Senegal international remains hot property in the transfer market after his 16 goals and five assists in 31 Serie A games for Lazio last season.
Balde has just one year remaining on his Lazio contract and has been linked with a number of clubs this summer and according to La Repubblica, Chelsea have cast their eye upon him as he offers more than one playing positions.
He certainly is more versatile than Lukaku as he can play either as a right or left winger, an attacking midfielder and also as a centre forward.
After being beaten by Manchester United to their top target, Romelu Lukaku, Antonio Conte's side is desperate for a forward to fill the void left by Diego Costa.
However, the offer looks unlikely to be accepted as Lazio president Claudio Lotito is reportedly insisting on a £26.5 million fee.
Milan had initially agreed terms with Lazio but Keita rejected the transfer, as his heart was set on a move Juventus.