Vincenzo Montella's men scraped past their lowly opponents, but the victory was marred by a nasty injury to their star striker.
The Viola struggled to pin their opponents down at the Artemio Franchi and almost fell behind when Ibrahima Mbaye rattled the crossbar, but just two minutes later defender Gonzalo Rodriguez gave his side the lead as he rose tallest to meet Borja Valero’s inswinging corner.
Vincenzo Montella’s men withstood a late siege to their goal, as Rodriguez cleared off the line and Norberto Neto was forced into a couple of fine stops, but victory was overshadowed as Rossi had to be helped off with what looked like a serious knee injury, after a challenge from center back Leandro Rinaudo.
After the game, Fiorentina confirmed what many had feared - that the injury sustained had been to the same knee that had caused Serie A’s leading scorer problems in the past - however the full extent would not be revealed until Monday.
"AFC Fiorentina announce that, as a result of a collision with Livorno player Rinaudo during the game, Giuseppe Rossi has suffered a sprain to his knee which was previously operated on," the club website stated. "Diagnostic tests will be carried out tomorrow."
The injury comes as a bitter blow for a player who had began this season by ending a 23-month-long goal drought, with several of those months being spent in the treatment room after interior cruciate ligament injuries to the same knee.
Originally keeping him out for six months in 2011, a recurrence of the ligament damage in training saw Rossi miss an additional 10 months while at Villarreal.
Any repetition this time around would surely put a disappointing end to any World Cup dreams the New Jersey-born striker was harboring – news that would be nearly as concerning for Italy coach Cesare Prandelli as it would for Rossi.