PSG host relegation battling Le Havre on Saturday
Second-half goals from Jose Callejon and Lorenzo Insigne in the second leg of the playoff tie ensured that Serie A will have three teams in the group stage.
Sevilla suffered a fright, going 1-0 down at home to Istanbul Basaksehir, before drawing 2-2 to win 4-3 on aggregate.
Former European champions Celtic also progressed when they won 8-4 on aggregate against Kazakhstan's Astana, although they lost the second leg 4-3 and at one stage trailed 4-1.
Slovenian champions Maribor overcame Israel's Hapoel Beer-Sheva on away goals after a 1-0 win in the second leg and Olympiakos beat Rijeka 1-0 away to qualify 3-1 on aggregate.