Three own goals were scored as Napoli's spectacularly inconsistent season continued with a 4-2 defeat at Empoli on Thursday, leaving them five points adrift of a Champions League qualifying place.
Rafael Benitez's side stayed fourth with 56 points while AS Roma, who won 3-0 at Sassuolo on Wednesday, have 61 in third, which earns a place in the Champions League playoff round.
Napoli quickly undid Sunday's good work, when they revived their Champions League hopes with a 4-2 win over Sampdoria, as they conceded three goals before halftime against Empoli, who have spent the season in the lower half of the table.
Massimo Maccarone put Empoli ahead in the eighth minute when the player known as 'Big Mac' finished off a neat move by firing a powerful low shot under goalkeeper Mariano Andujar.
The hosts went further ahead in bizarre fashion in the 43rd minute when Riccardo Saponara crossed from the byline, Andujar fisted the ball away and it hit Miguel Britos in the face and rebounded into the net from point-blank range.
Two minutes later Manuel Pucciarelli wriggled his way into the area and, although his shot was beaten away by Andujar, the rebound went to Saponara who brilliantly hooked the ball into the goal with an acrobatic volley.
Napoli, who had won their previous three league games, pulled one back when the Empoli keeper's attempted clearance hit Vincent Laurini and bounced into the net for another unusual goal in the 64th minute.
But their fightback was cut short when defender Raul Albiol unwittingly turned an Empoli free kick into his own goal nine minutes later to make it 4-1. Marek Hamsik pulled another goal back amid the home side's claims of offside but it was too late to save Napoli. Empoli's win moved them up a place to 15th with 38 points.
Napoli could still qualify for the Champions League by winning the Europa League, having reached the semi-finals where they face Dnipro Dnipropetrovsk -- the only way of saving a season in which they are regarded as having under achieved.