The 24 year-old was one of two marquee arrivals at St. Mary's prior to the 2017-18 season, alongside centre-half Wesley Hoedt, and became a swift pioneer in the club's eager battle against a potential relegation to the Championship.
Jorginho is set for a move to Premier League champions Manchester City and Napoli aim Lemina to be the Brazilian's replacement - it would also be the first signing of recently appointed manager Carlo Ancelotti in Naples.
Despite a minor injury mid-way through last term, the ex-Marseille player tallied up 29 appearances in all competitions for Southampton since he penned a five-year deal last August and has seemingly been one of just a handful of bright sparks in the Saints camp over the past twelve months - catching the eye of Liverpool in the winter transfer window.
Mario Lemina failed to make a name for himself during his time at Juventus in the two years he spent there but would be aiming to prosper with a potential transfer to Napoli went through.
Disaster would strike with Lemina departure
It is fairly unarguable that last season was nothing short of a catastrophe for the Saints, as Mark Hughes steadied the ship and will be anticipating to build on the team's thankful escape but that may take a large blow if Mario Lemina was to exit.
Having found the back of the net just once last campaign, the midfielder often found himself playing alongside Spaniard Oriol Romeu in the heart of the formation; regularly pushing forward and becoming a threat to opposing defences.
Lemina is one of the highlights of the previous term for Southampton and his absence is inexcusably noticeable; Hughes and the supporters would feel the real brunt of his departure if Napoli did happen to snatch their man this summer.
If there's any positive news for Saints fans to boast about it is the envisaged acquisition of Stoke City man Xherdan Shaqiri, who will be likely to leave the recently relegated outfit in search of retaining top-flight football but do face competition from Tottenham Hotspur.
Mark Hughes has also reportedly been sniffing around Everton forward Ademola Lookman after the youngster's talented performances in Germany during his loan stint at RB Leipzig, however, the appointment of Marco Silva at Goodison Park may halt Southampton's race for the 20-year-old's signature.
Both are attacking propositions that would undoubtedly improve the current attacking ranks on the south coast - as well as Mark Hughes dumping some of the dead wood within the camp from the club's retained list, released last week - the first-team are set for an exciting transfer window ahead as they build for a hopeful 2018-19 season.