Wednesday's home defeat to the Greeks was painless as Inter qualified for the Champions League last 16 courtesy of results elsewhere but it proved that the inconsistency the Italian champions have shown this season was not buried by last weekend's well-earned 1-0 win over Juventus, which sent them three points clear.
"After this result we have to present ourselves at our stadium against Napoli on Sunday with the right drive and with anger to play a different match from the one we deservedly lost to Panathinaikos," Mourinho was quoted as saying on the club's website (www.inter.it).
Napoli, who are six points behind Inter in fourth, will also have some frustration to vent after losing ground last Sunday with a 2-2 home draw with Cagliari when they conceded a goal in stoppage time.
Their hopes of upsetting Inter will revolve around 23-year-old Argentina forward Ezequiel Lavezzi, who has been inspirational in their rise to the upper reaches of Serie A this season and scored a splendid free kick against Cagliari.
Second-placed AC Milan travel to Palermo without suspended Brazil playmaker Kaka who, according to coach Carlo Ancelotti, will be badly missed despite not having regained his best form after missing the start of the season with a knee injury.
"Kaka is irreplaceable even when he isn't playing at his best," Ancelotti told reporters ahead of Milan's UEFA Cup tie at Portsmouth on Thursday.
Dutch midfielder Clarence Seedorf is tipped to move forward to take Kaka's place alongside the in-form Ronaldinho in support of a lone striker, who is likely to be Alexandre Pato.
Milan's Kakha Kaladze risks a suspension after being charged by the Italian Football Federation for saying Stefano Farina was a poor referee following Sunday's 2-2 draw at Torino.
The Georgian was unhappy that Farina gave a late penalty that cost Milan victory for his handball while failing to grant a spot kick for a similar incident at the other end.
The club are hoping Kaladze will get away with a fine as they subsequently told their players to stop criticising officials and the defender apologised.
On Saturday third-placed Juventus entertain third-from-bottom Reggina, whose troubles have been eased by two consecutive wins.
Last season's runners-up AS Roma are seeking to continue their recovery from a miserable start with a home win over Fiorentina on Sunday.
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