Second-half goals from Jose Callejon and Lorenzo Insigne earned Napoli a 2-0 win in Nice and ensured their qualification for the Champions League group stages.
The Serie A side won 4-0 on aggregate but it could have been more with Dries Mertens also striking the post and missing several opportunities in a game they largely dominated.
After a frustrating first half, Callejon opened the scoring from close range in the 48th minute from a Marek Hamsik cross while Mario Balotelli was on the sideline receiving treatment.
Insigne's well-placed effort from the edge of the box in the 89th minute wrapped up proceedings.
Nice, who started with Balotelli, Wesley Sneijder and reported Barcelona target Jean Seri in their side, did rally after going behind but were unable to break down a superior side.
The Ligue 1 outfit will now play in the Europa League for a second consecutive campaign.
Sevilla overcame a scare from Istanbul Basaksehir to advance 4-3 on aggregate after a 2-2 draw.
After Gabriel Mercado hit the post for the Spanish club, the visitors took a shock lead as Emmanuel Adebayor played in Junior Caicara, whose cross found Eljero Elia in the 17th minute.
That put the Turkish side ahead on away goals, and Sevilla needed to wait until the second half to regain control as Sergio Escudero headed home from a Jesus Navas cross in the 52nd minute.
Wissam Ben Yedder then supplied some breathing room from a tight angle on 75 minutes after some good control by Nolito.
And it would prove to be a needed goal as Edin Visca got a goal back in the 83rd minute, but Basaksehir could not find another, though Emre Belozoglu cracked the post in stoppage time.
Celtic slipped to a surprise 4-3 defeat against Astana in Kazakhstan but qualified 8-4 on aggregate thanks to their 5-0 first leg win.
There were some nervy moments for the Scottish champions as they slipped to a first defeat of the season in a pulsating encounter at the Astana Arena.
Celtic's 19-year-old defender Kristoffer Ajer, in for injured Jozo Simunovic, deflected a shot from defender Dmitri Shomko past goalkeeper Craig Gordon in the 26th minute to put the Kazakh side in front, but Scott Sinclair had Celtic level eight minutes later.
Two goals in a minute at the start of the second-half from attackers Serikzhan Muzhikov and Patrick Twumasi brought the home side back to life and, when Ghanaian Twumasi grabbed his second to make it 4-1, the visitors were on the ropes.
However, late goals from Olivier Ntcham and Leigh Griffiths confirmed Brendan Rodgers' side's passage into the group stages for the second successive season.
Olympiakos confirmed their participation in the Champions League group stage with a 1-0 win away to Croatian champions Rijeka.
Former Chelsea winger Marko Marin scored the only goal of the game in the 25th minute, scoring from an angle following a ball from Vadis Odjidja-Ofoe.
That ensured the Greek side a 3-1 aggregate win and a return to the Champions League after they fell at this stage last season.
Maribor advanced on away goals after securing a 1-0 win over Hapoel Be'er Sheva.
Mitja Viler scored the only goal of the night after a cross from the endline deflected out to him to just inside the box, and he lashed home in the 15th minute.
That ensured the Slovenian champions reached the group stage 2-2 on aggregate after their 2-1 win in Israel last week.