The two clubs have been locked in negotiations for several weeks, but it appears they have finally sorted out all details.
Tuttosport claims Fiorentina will sign the player on loan until the end of the season, with an option to buy 50% of the player’s contract for €1.5 million.
Larrondo, 24, is currently undergoing a medical at Artemio Franchi, with the deal set to be officially unveiled later today.
This is quite a surprising move for Fiorentina considering that the Argentine striker has made just three league appearances for Siena this season and that he has yet to prove his worth at the highest level.
Viola boss Vincenzo Montella, nonetheless, believes the former River Plate footballer has what it takes to succeed in Florence and will use next six months to take a closer look at the player.
Marcelo Larrondo has made a total of 59 Serie A appearances for Siena and scored 8 goals in the process.