Why this Serie A match next week is so important

Napoli and AC Milan have to face each other in the Champions League round of 16. However, less than 2 weeks before that encounter, they have to play each other in the Serie A. Ordinarily, this match would not seem as important, as Napoli are 23 points clear of Milan. But, this match will have a large mental effect, with the winning team going into the Champions League match far more confident just 10 days later. Interestingly, the second leg game will actually be the third between the two sides in less than 3 weeks.