While Juve have taken just two points from the last 12 available but beat Lazio on Tuesday, the Viola also won their first leg amid faltering form in the top flight.
Match preview
Second-half strikes from Federico Chiesa and top scorer Dusan Vlahovic put Juventus in charge of their semi-final tie in the Coppa Italia, as they will take a two-goal advantage to Rome for the second leg later this month.
Just days after suffering a last-gasp league defeat to Lazio in the capital, Juve managed to turn things around on home soil, so silverware remains a possibility despite their dismal form since mid-winter.
Recent results have seen Max Allegri's men slide to third place in the standings, with champions-elect Inter Milan streaking off into the distance and AC Milan overtaking the Turin giants of late.
In fact, Juventus are 20 points from the top at this late stage of a season for only the second time in their long and illustrious history, causing speculation regarding Allegri's future to swell.
The Bianconeri's winless streak stands at four Serie A matches, so after posting an increasingly rare clean sheet in the cup, they will aim to continue their relatively solid home record.
Having lost only one of 15 league fixtures at the Allianz Stadium this term, Juve now host one of the clubs that loathe them most: a series of Fiorentina players - most notably Roberto Baggio - have trodden the path from Florence to Turin, creating a bitter enmity.
Most recently, Vlahovic (98 league games and 44 goals for the Viola) and Chiesa (137 and 26) have opted to leave Stadio Franchi for the lure of Juventus - but neither has been directly involved in any goals against their old side since.
Fiorentina have lost 11 of their last 12 away matches against Juventus, failing to even score in four of the last six, and they were also beaten 1-0 by the Bianconeri in November's reverse fixture.
Like their old foes, the Viola rank inside Serie A's bottom half for games played during the second half of this season - Juve sit 11th, with Fiorentina five places below them - so cup competitions may also prove their only route to success.
Vincenzo Italiano's side could meet Juventus in the Coppa Italia final, following a 1-0 first-leg defeat of Atalanta BC on Wednesday evening, when Rolando Mandragora notched the only goal and La Dea's Marco Carnesecchi kept the scoreline down with a series of saves.
Set to kick off their Europa Conference League tie with Viktoria Plzen next week, Fiorentina lost in two finals last term, so Italiano will be keen to go one better this time around, before departing in the summer.
On Sunday, when they will try to rekindle faint hopes of returning to Europe via Serie A, the Viola must attempt to improve some dire away form, having picked up just 16 points from 42 available on their travels this season.
Finally ending their five-match streak without a league win on the road - a run that stretches back to December - is perhaps asking too much from a side that tends to falter when leaving Tuscany.
Juventus Serie A form:
D
W
L
D
D
L
Juventus form (all competitions):
W
L
D
D
L
W
Fiorentina Serie A form:
L
D
W
D
D
L
Fiorentina form (all competitions):
D
W
D
D
L
W
Team News
While back-up goalkeeper Mattia Perin returns to the bench and first-choice Wojciech Szczesny replaces him, Juventus boss Max Allegri is not expected to make many other changes to his lineup this weekend.
With Arkadiusz Milik still ruled out by injury, Dusan Vlahovic starts up front: Juve's win percentage drops from 64% to 20% without the Serbian striker and their goals-per-game ratio is halved.
Vlahovic has racked up 15 league strikes to sit second in the Capocannoniere rankings this season, but he has yet to score in five games against Fiorentina since leaving.
Meanwhile, the Viola's central striker Andrea Belotti has netted a modest four times versus Juventus to date, though one came on his last visit to the Allianz Stadium with former club Torino.
Vincenzo Italiano rotated his resources for the cup win over Atalanta, dropping Giacomo Bonaventura into a deeper midfield position and selecting Fabiano Parisi at left-back, with Christian Kouame making rare consecutive starts on the wing.
After Oliver Christensen was back on the bench in midweek, and Bonaventura's Serie A suspension was served in last Saturday's 2-1 defeat to Milan, the visitors should have a full squad available on Sunday evening.
Juventus possible starting lineup:
Szczesny; Gatti, Bremer, Danilo; Cambiaso, McKennie, Locatelli, Rabiot, Kostic; Chiesa, Vlahovic
Fiorentina possible starting lineup:
Terracciano; Kayode, Milenkovic, Martinez Quarta, Biraghi; Bonaventura, Arthur; Gonzalez, Beltran, Sottil; Belotti