Under-pressure Arsenal will compete in the UEFA Champions League for the 14th consecutive season, securing their place with a come-from-behind victory over Udinese in Italy, while former champions Benfica also reached the group stage.
Defending a slim 1-0 advantage from the first leg of their play-off tie, Arsenal, having endured a poor start to the English Premier League season, which has yielded just one point and no goals, found themselves a goal behind in the 39th minute.
Antonio di Natale levelled the tie on aggregate with a header inside the right-hand post. However, Arsenal captain Robin van Persie equalised ten minutes into the second half, before Udinese squandered a golden opportunity to go ahead when they were awarded a penalty for a Thomas Vermaelen handball in the area.
Arsenal goalkeeper Wojciech Szczesny dived to his right to keep out Di Natale's spot-kick and the Londoners took full advantage when Theo Walcott put the tie out of reach in the 69th minute. It was enough to secure victory on a day when Samir Nasri completed his move away from Arsenal to Manchester City and just nine days after Cesc Fabregas returned to Barcelona.
"We showed that, under pressure, we can respond with football and remain calm and composed on the ball and play like we know how to play," Arsenal coach Arsene Wenger told ITV.
Witsel lifts Benfica
Belgian international Axel Witsel scored twice as former champions Benfica defeated Dutch league leaders FC Twente 3-1 at the Stadium of Light for a 5-3 aggregate success following a 2-2 draw in Holland last week. Witsel, signed from Standard Liege in the summer, found the target in the 46th and 66th minutes, with Luisao also on the score-sheet on the hour mark.
Lyon will play in the group stage for the 12th successive season after a tense 1-1 draw at Rubin Kazan in Russia put them through 4-2 on aggregate. Bebras Natcho scored for Rubin with 13 minutes remaining and the Russian side sensed a famous night as another goal would have put them through on the away goals rule.
However, new signing Bakary Kone headed home with three minutes left to make sure of Lyon's place in Thursday's draw.
"It's a relief and a satisfaction to be qualified for the Champions League," said Lyon coach Remi Garde. "I started to worry when we missed a couple of chances. When you squander good opportunities, it gives the opposition confidence."
Also going through on Wednesday were Czech side Viktoria Plzen, who saw off Copenhagen 2-1 to secure a 5-2 aggregate win and a first appearance in the lucrative group stage.
Thursday's group-stage draw will feature the ten play-off winners and the 22 automatic entrants. One of those teams will be Trabzonspor, who on Wednesday took the place of Turkish league winners Fenerbahce after their rivals were banned due to an ongoing match-fixing probe that has ensnared the Istanbul club.