The 20-year-old is a product of the Argentinian side’s academy and has impressed since making the step up into the first team.
Mammana’s form has attracted the attention of a host of top European clubs with Chelsea leading the race for the centre-back.
However, according to L’Equipe, Lyon are preparing a bid of their own in an attempt to steal a march on the Blues.
Incoming Chelsea boss Antonio Conte first became aware of the Argentina under-20 international during his time in charge of Juventus, with Serie A clubs Fiorentina and Napoli apparently keen on the player.
And the Italian has reportedly instructed his Chelsea staff to scout the young star further, before Lyon snap him up from under their noses.