Milan made five changes for the win over Sparta Prague and boss Stefano Pioli says it is becoming more difficult to choose his best side.
Milan's 100 per cent start to the season in Serie A was ended by Roma after a 3-3 draw in which Zlatan Ibrahimovic scored twice.
Gianluigi Donnarumma has enjoyed a fine start to the 2020-21 season but could now sit out games due to coronavirus.
Juve needed a late leveller from Dejan Kulusevski against Hellas Verona and boss Andrea Pirlo was not impressed by his side's display.
Juventus went into isolation earlier this month due to coronavirus cases and, according to the club, talks with Paulo Dybala were impacted.
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