Galatasaray have hung on to their lead and Young Boys survived having the frame of their goal struck three times to but end Tuesday back in the Champions League group stage.
Galatasaray defender Angelino's deflected free kick in added time sealed a 2-1 win over Molde in the second leg of their qualifying play-off, and a 5-3 aggregate score, minutes after the Norwegian champions had a possible equalising goal overruled by VAR.
Young Boys eventually eased past Maccabi Haifa 3-0, after a scoreless draw in Israel last week, though the Swiss champions rode their luck in the first half.
Braga also booked their place in Thursday's 32-team group stage draw by winning 1-0 at Panathinaikos to complete a 3-1 aggregate score.
Once Champions League regulars, Galatasaray will be back on the elite stage for the first time since 2019 having come through three qualifying rounds.
Argentine striker Mauro Icardi scored for the third straight game, including in the 3-2 win in Norway last week, when he converted a penalty in the seventh minute.
Molde, once the club of a teenaged Erling Haaland, pressed hard in the second half and Eirik Hestad pulled a goal back midway through the second half. Though Veton Berisha put the ball in Galatasaray's net in the 81st, an offside was spotted on review.
Young Boys will play in the group stage for the third time in six seasons. They got home wins against Juventus and Manchester United in 2018 and 2021, respectively, though never advanced to the knockout rounds.
The Swiss team took control against Maccabi Haifa when Congolese winger Meschack Elia sent in crosses that led to two goals in four minutes midway through the first half.
The win was secured in the first minute of the second half when Filip Ugrinic's shot was deflected into the Maccabi net.
Braga's return to the group stage after an 11-year absence was settled by Portugal international forward Bruma finishing off a counter attack in the 83rd, in front of more than 61,000 at the Olympic Stadium in Athens.
Galatasaray, Young Boys and Braga are now guaranteed prize money of about 20 million euros ($A34 million) from UEFA, with bonuses for wins and draws in the group stage.
Molde, Maccabi Haifa and Panathinaikos switch across to the second-tier Europa League group stage.