Honours even in Naples
Napoli were held to a goalless draw by Spanish side Villarreal in the first leg of their Europa League last-32 showdown in Naples.
The Italians, who lie second in Serie A after an impressive campaign so far, struggled to get past Villarreal's massed defence and had to settle for a scoreless result.
The hosts ended the game down to 10 men after Salvatore Aronica was sent off with a minute remaining for a second bookable offence when he needlessly fouled Villarreal's Nilmar.
Napoli coach Walter Mazzarri named a first-choice team with Ezequiel Lavezzi partnering the team's top scorer Edinson Cavani up front.
However, Cavani, who has scored seven times in Europe this campaign, could not find a way through to Villarreal's goal.
It was the visitors who threatened first in the 14th minute when Giuseppe Rossi set up Nilmar and he fired in a shot from 30 yards that was kept out by Napoli goalkeeper Morgan De Sanctis.
His opposite number Diego Lopez was soon in the action, palming over a long-range effort from Hugo Campagnaro before Cavani also stung his palms with a right-footed strike from outside the area.
On the stroke of half-time, Villarreal defender Gonzalo did well to block Cristian Maggio's goalbound effort from the centre of the penalty area.
Napoli pushed forward more aggressively after the restart and almost broke the deadlock in the 52nd minute when Maggio's powerful eight-yard header from Lavezzi's cross went wide.
Shortly before the hour mark, Lavezzi struck over the bar from a good position as another chance went begging.
In the 72nd minute, Borja Valero almost punished the Italians but his right-footed effort from the edge of the area went just wide of the far post.
At the other end, Campagnaro fed Lavezzi inside the area and his shot was met by a fine save from Lopez.
Nilmar then wasted a good chance to put Villarreal in front when he latched on to Borja Valero's pass only to fire way off target from 10 yards.
Villarreal could have ended Napoli's unbeaten run at the San Paolo Stadium this season in the Europa League with one minute remaining.
However, De Sanctis stretched to repel Valero's stinging drive from 30 yards in what was the last chance of the game.
Napoli travel to El Madrigal stadium on February 24 with all to play for.