Inter stayed clear at the top in Italy by beating Atalanta last weekend, then sealed their place in the Champions League's last 16; their promoted visitors, meanwhile, find themselves closer to the top six than the drop zone.
Match preview
After extending their unbeaten run to seven matches with a 2-1 win over regional rivals Atalanta last time out in Serie A - keeping them two points above closest pursuers Juventus - Inter went on to secure a top-two finish in Group D of the Champions League with two games remaining.
The Nerazzurri's irrepressible form of October has therefore carried over into a new month, and having lost just once this term they are firmly on course to challenge for silverware again, after lifting the Coppa Italia and narrowly missing out on European glory in the spring.
Over the last 19 rounds of Serie A - effectively half a season - Inter have posted 16 wins and just two defeats, keeping 11 clean sheets and picking up 49 points in total. During that time, their closest rivals are Milan and Juventus - both with 10 points fewer.
There is no doubt that Simone Inzaghi's side have established themselves as most pundits' Scudetto favourites, as after Hakan Calhanoglu's latest successfully converted spot-kick and a Lautaro Martinez strike helped Inter see off Atalanta, their record in 2023-24 is unmatched.
Not only have they scored the most goals overall (27), the most second-half goals (17), and more from set-pieces than any other side (eight), the second-city club have also conceded the fewest times from open play (five).
Free-scoring skipper Martinez was on target again in Salzburg on Wednesday, and he now aims to sign off for international duty by adding more to his tally against one of Serie A's minnows.
There will, of course, be a chasm between two clubs of very different stature when Inter and Frosinone meet for Sunday's late kickoff, and the Milan giants have won all four of their previous top-flight encounters with the Canarini to date - scoring 11 times and conceding just once.
Nonetheless, last term's Serie B champions will arrive at San Siro buoyed by a brilliant start to life back among Italy's elite, most recently celebrating two wins in the space of a week.
Having thrown away a three-goal lead to lose against fellow promoted club Cagliari a fortnight ago, Eusebio Di Francesco's squad showed their mettle by beating Torino in the Coppa Italia - setting up a last-16 clash with Napoli - and then taking maximum points against Empoli on Monday.
German teenager Arijon Ibrahimovic - one of numerous young loanees at Stadio Stirpe this season - struck in both games to put that familiar surname up in lights once again, and no less than five of the 17 players born in or after 2001 who have scored a Serie A goal this term represent Frosinone.
The portents look good for the Lazio-based club, who have already accrued 15 points to sit safely in mid-table: of the last 28 promoted teams to post as many points after 11 rounds, only one suffered relegation at the end of the season.
Inter Milan Serie A form:
L
W
D
W
W
W
Inter Milan form (all competitions):
D
W
W
W
W
W
Frosinone Serie A form:
D
L
W
L
L
W
Frosinone form (all competitions):
L
W
L
L
W
W
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Team News
Inter defender Benjamin Pavard was forced off in the first half of last week's win over Atalanta with a knee injury, and he could be out of action until next year. Juan Cuadrado (tendinitis) also remains sidelined, but Marko Arnautovic is back in action and should start Sunday's game on the bench.
The absence of Pavard will most likely see Matteo Darmian or Yann Bisseck deputise on the right side of the hosts' back three - should Darmian get the nod from Simone Inzaghi, then Denzel Dumfries would return at wing-back.
After being deployed as a substitute in midweek, Lautaro Martinez should be fresh for the challenge of maintaining his superb scoring rate this season: the Argentina striker already has 12 goals from 11 Serie A matches, and the last foreign player to score at least 13 after 12 rounds was his compatriot Gabriel Batistuta, back in 1994.
Meanwhile, Frosinone's attack should be led by Marvin Cuni, who has recently replaced Napoli loanee Walid Cheddira as the Canarini's front man; in-form Arijon Ibrahimovic - borrowed from Bayern Munich - is set to support him.
Juventus-owned pair Matias Soule and Enzo Barrenechea will also feature for the visitors, for whom Abdou Harroui and Francesco Gelli remain unavailable due to injury.
Inter Milan possible starting lineup:
Sommer; Darmian, De Vrij, Bastoni; Dumfries, Barella, Calhanoglu, Mkhitaryan, Dimarco; Thuram, Martinez
Frosinone possible starting lineup:
Turati; Oyono, Romagnoli, Okoli, Marchizza; Mazzitelli, Barrenechea; Soule, Reinier, Ibrahimovic; Cuni
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