Juve pulled within a point of the Serie A leaders, going second in the table as Gonzalo Higuain - who played despite having surgery on a fractured left hand this week - scored his fifth goal in as many games against his former club.
Allegri told Mediaset Premium: "It was a good test tonight, the lads had some favourable situations in the first half and took the lead.
"Napoli kept a lot of possession in the second half and put pressure on, but we allowed them very little in terms of chances. If anything, Pepe Reina performed a miracle on Blaise Matuidi.
"Now we are one point behind Napoli, it's a good result, but we have to look forward now to Tuesday, as there is a place in the Champions League round of 16 at stake.
"We have to compliment Napoli, who put in a good performance, confirmed they are still the Scudetto favourites and play really pleasant football."
Winger Douglas Costa was influential on the counter-attack for Juventus, who prevailed despite missing Mario Mandzukic, Benedikt Howedes and Stephan Lichtsteiner through injury.
"Douglas Costa is an extraordinary player, he can do things on a technical level that few others can. Medhi Benatia is in good shape, but we need in general to be braver in playing the ball out of defence," Allegri added.
"I told the lads that normal effort and normal performances are not enough, we need extraordinary levels to match the extraordinary players in the squad.
3 - Napoli have lost only 3 of their last 45 Serie A games, 2 of these against Juventus. Nightmare. #NapoliJuventus— OptaPaolo (@OptaPaolo) December 1, 2017
"We had to remain organised and continue to direct Napoli towards the areas where they weren't going to cause us problems.
"Winning games isn't all about possession, but rather making the most of your strengths, identifying the weaknesses of your opponents and getting the best out of those situations.
"We have a group of extraordinary players who have done marvellous things are now trying to go beyond legend. We know that it takes something beyond the normal."