The Rossoneri were held by promoted Cremonese in midweek - their second straight stumble away from home - so will want to bolster their Scudetto defence by beating visitors running into top form just as the season stops for the World Cup.
Match preview
Only days after scrapping out a home win against Spezia thanks to Olivier Giroud's late winner, Milan found themselves frustrated by a Cremonese side yet to win since returning to Serie A in the summer and languishing in the relegation zone.
Tuesday's encounter in Cremona saw Stefano Pioli's men totally dominate possession, but a combination of sound goalkeeping and profligate finishing resulted in a scoreless stalemate that allowed Lazio to leapfrog them into second place in the standings.
Despite the appearance of Qatar-bound duo Rafael Leao and Charles De Ketelaere from the bench after the break, a Milan attack led by Divock Origi - who has not been selected by Belgium - failed to break through their hosts' stubborn defence.
Following defeat in their previous away game - at Torino, late last month - the champions have therefore picked up just one point from the last possible six on the road, which contrasts starkly with their fine form at San Siro.
Milan have averaged 2.3 goals per game in their last 10 Serie A home games, winning nine times in the process and suffering only a solitary loss to unbeaten leaders Napoli; keeping a clean sheet in half of those fixtures.
Pioli, who oversaw 69 top-flight matches as Fiorentina coach between 2017 and 2019, will be keen to now take advantage of finishing the first phase of Milan's campaign at their imposing home ground - a venue where they defeated Sunday's visitors 1-0 in the teams' most recent meeting, when they surged towards the title back in May.
Curiously, Fiorentina have lost only one of their last 11 Serie A matches against Milan in the first half of the season, despite generally having the inferior tally in the clubs' head-to-head record.
They may fancy their chances of extending such a run on Sunday evening, as a recent resurgence sees them back into the top half of the table just before the World Cup break, and also through to the Europa Conference League's knockout stages.
The return of summer signing Luka Jovic to something approaching his best form has played a significant part for a side that simply could not convert their chances and make their dominance of the ball pay, and the Serbian striker was on target again in midweek, as the Viola secured a 2-1 win over Salernitana via his 81st-minute winner.
That brought up a fifth straight win in all competitions for Vincenzo Italiano's men, who had beaten Spezia, Sampdoria and Latvian outfit RFS in a three-game road trip before returning to Florence on Wednesday.
Fiorentina are, in fact, unbeaten in each of their last three Serie A away games too, and would make it four in a row for the first time under Italiano if they can cause an upset this weekend.
Under the leadership of ambitious owner Rocco Commisso, the Viola cannot settle for being eight points adrift of the European places, so will seek to continue their steely resolve when playing away from home: they have conceded just six goals in seven Serie A away fixtures so far and average over a point per game.
AC Milan Serie A form:
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AC Milan form (all competitions):
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Fiorentina Serie A form:
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Fiorentina form (all competitions):
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Team News
After fielding an unfamiliar formation and some second-choice personnel in midweek, Stefano Pioli should select the strongest starting XI available to him on Sunday.
France internationals Theo Hernandez and Olivier Giroud are both back from suspension and will return to the side; therefore, Fode Ballo-Toure and Divock Origi make way. Giroud has scored four goals in his last four appearances, and Milan have won 17 of 18 games in which he has found the net since signing last year.
Rafael Leao began Tuesday's game on the bench, but now returns on the left side of the hosts' front three, having scored twice in three previous Serie A meetings with Fiorentina - including his very first goal in the Italian top flight, back in September 2019.
Once more, goalkeeper Mike Maignan joins Davide Calabria, Sergino Dest, Alexis Saelemaekers, Alessandro Florenzi and Zlatan Ibrahimovic in a crowded treatment room at Milanello; Junior Messias is also a doubt.
Fiorentina's injury list, meanwhile, features Argentinian winger Nicolas Gonzalez, fellow wide man Riccardo Sottil and long-term absentee Gaetano Castrovilli.
After Arthur Cabral started up front on Wednesday, Luka Jovic is likely to lead the line at San Siro, while his supporting cast could include former Milan men Riccardo Saponara and Giacomo Bonaventura - the latter scored 30 goals in 155 Serie A matches for the Rossoneri between 2014 and 2020.
AC Milan possible starting lineup:
Tatarusanu; Kalulu, Tomori, Kjaer, Hernandez; Tonali, Bennacer; Krunic, Diaz, Leao; Giroud
Fiorentina possible starting lineup:
Terracciano; Dodo, Milenkovic, Martinez Quarta, Biraghi; Amrabat, Mandragora; Ikone, Bonaventura, Kouame; Jovic