Napoli were without their top scorer Victor Osimhen, as they lost 1-0 at AC Milan in the first leg of their Champions League quarter-final on Wednesday night.
Ismael Bennacer gave the hosts the advantage over the runaway Serie A leaders, as the visitors had Frank Anguissa sent off in the second half.
Bennacer scored a first-half winner as he hammered past Alex Meret to put Milan on course for a first Champions League semi-final since 2007, when they won the competition.
Napoli, who are 22 points ahead of Milan in Serie A but were without injured star striker Victor Osimhen for the first leg, had spells of dominance at the San Siro as they saw an effort cleared off the line in the first minute and hit the bar in the second half.
But Anguissa picked up two yellow cards in the space of three minutes and 45 seconds to see red in the 74th minute to halt their momentum, although Giovanni Di Lorenzo saw an effort well saved by Mike Maignan late on.
