Arturo Vidal conceded a penalty against Crotone before he was hooked at half-time, prompting criticism from Inter coach Antonio Conte.
Inter accelerated away from poor Crotone in the second half of Sunday's San Siro clash to at least briefly take top spot in Serie A.
Juventus supporters can expect more mistakes as their young side takes shape, according to boss Andrea Pirlo.
Juventus dropped points for the second time in four Serie A games this season as newly-promoted Crotone held them to a draw on Saturday.
Cristiano Ronaldo tested positive for COVID-19 while on international duty with Portugal and will isolate at home after returning to Turin.
Siku kiri Ante Rebic terkehel ketika memperkuatkan Milan menentang Crotone dan mujur dia tidak dilanda kecederaan lebih serius -- patah tulang -- demikian umum Milan malam tadi.
Ante Rebic sustained a nasty looking arm injury against Crotone, but Milan head coach Stefano Pioli hopes he will return promptly.
Despite being without Zlatan Ibrahimovic, Milan made it four wins from four in all competitions this season as they saw off Crotone.
Milan would rather have Zlatan Ibrahimovic available, but without him at Crotone there will be a chance for others to impress.
A 5-1 thrashing of Livorno was enough to secure Crotone's place in Serie A for the first time since 2017-18.