While the Biancorossi were denied a place in the Coppa Italia quarter-finals by Juventus, they were 12 points clear of danger after 18 rounds; their visitors' faltering form has dropped them down to 17th.
Match preview
Having toppled the Old Lady in the clubs' first top-flight meeting earlier this term, Monza sought to repeat the trick in Turin on Thursday night but came up just short in their quest to seal a Coppa Italia quarter-final tie with Lazio.
After Juve's Moise Kean and Mattia Valoti scored first-half headers, it was the hosts' returning hero Federico Chiesa who leapt off the bench to curl in a 78th-minute winner; ending Monza's dreams of a first piece of major silverware.
When former Juventus winger Raffaele Palladino stepped in as the Biancorossi's caretaker boss early on in the season, it seemed they would be set for a gruelling battle against swiftly returning to Serie B, but the rookie coach has forged a team capable of mixing it with the best.
Making the most of some ambitious summertime acquisitions, Palladino has recently steered his side to an unbeaten run of four league games, and they are the first team to post as many as 21 points from the first half of their first-ever Serie A season since 2004.
Last Saturday's 3-2 win at Cremonese hauled the Lombardy club further clear of danger - after they had previously held Inter and Fiorentina to draws - and they now host a side short of confidence and heading in the opposite direction.
Sitting five points behind Sunday's opponents, Sassuolo have now lost their last four league games, and only once before have they gone on a run of at least five consecutive Serie A defeats.
Still in search of their first point of 2023, the Neroverdi were beaten 2-0 at Lazio last time out and are only once place above the drop zone as a result.
Head coach Alessio Dionisi - who lost some key players in the summer - is under pressure to produce an improvement, and a serious lack of firepower is front and centre of the reasons why his job could ultimately be on the line.
Such ill fortune in the final third has seen his side pick up just 16 points so far, and in their top-flight history, Sassuolo have always finished the first half of the season with at least 17.
Since September, the Emilians have failed to win a single away game too, so surely something must change soon if Dionisi is to remain in post and they are not to be drawn into a dogfight.
Monza Serie A form:
W
L
W
D
D
W
Monza form (all competitions):
L
W
D
D
W
L
Sassuolo Serie A form:
L
D
L
L
L
L
Sassuolo form (all competitions):
D
L
L
L
L
L
Team News
After making numerous changes for their midweek Coppa Italia tie, Monza are set to revert to a more familiar lineup on Sunday.
Therefore, back-up striker Christian Gytkjaer and reserve goalkeeper Alessio Cragno are among those likely to miss out; Andrea Petagna and Michele Di Gregorio should slot back in.
Forward pair Dany Mota and Gianluca Caprari are doubtful due to muscular issues, but Nicolo Rovella returned to the squad on Thursday and wing-back Samuele Birindelli is back from suspension.
Meanwhile, Sassuolo regulars Andrea Consigli (knee) and Andrea Pinamonti (thigh) have both been ruled out by injury until next month, so Gianluca Pegolo will deputise for the former in goal and Agustin Alvarez replaces Pinamonti up front.
French forward Gregoire Defrel offers an alternative option for a goal-shy side, while his compatriot Maxime Lopez may now be ready to start after making a cameo from the bench last weekend.
Monza possible starting lineup:
Di Gregorio; Izzo, Mari, Marlon; Birindelli, Pessina, Ranocchia, Augusto; Colpani, Ciurria; Petagna
Sassuolo possible starting lineup:
Pegolo; Toljan, Erlic, Ferrari, Rogerio; Frattesi, Lopez; Berardi, Traore, Lauriente; Alvarez