Former European Cup winners Red Star Belgrade reached the Champions League group stage for the second successive season after a 1-1 home draw with Swiss side Young Boys in the playoffs sent them through on away goals on Tuesday.
They were joined by Croatian champions Dinamo Zagreb who advanced with a 1-1 draw at Rosenborg following a 2-0 first-leg win. Olympiakos Piraeus won 2-1 at Krasnodar to complete a 6-1 aggregate drubbing of the Russian side.
Roared on by a fervent 50,000 home crowd, 1991 European champions Red Star, who earned a 2-2 draw in the reverse fixture, were on the back foot for long spells but coach Vladan Milojevic was delighted after they squeezed through.
"I am very proud of my players and what we achieved this evening is a tremendous success," Milojevic told a news conference.
"It was tough. I told the players before the match that giving it their best shot was all anyone could ask for. We are now looking forward to our second season among Europe's elite.
"We are one big happy family at Red Star and still living the dream. We've made Serbia proud."
Left-back Milan Rodic missed Red Star's best chance in the first half when he headed over the bar before midfielder Michel Aebischer twice went close to swinging the tie Young Boys' way.
Red Star keeper Milan Borjan almost spilled a deflected cross into his own net and then saved a Roger Assale sitter before the home side broke the deadlock with their first purposeful move of the night.
Playmaker Marko Marin released Rodic with a delightful pass and the left-back raced down the flank to deliver a sharp cross for winger Aleksa Vukanovic to head home powerfully from six metres at the near post and score his first goal for Red Star.
The Serbian champions endured a tense last 10 minutes after they half-cleared a deep cross into their penalty area and substitute El Fardou Ben turned a shot by the visitors' Saidy Janko from 18 metres into his own net.
Borjan, who was instrumental in the previous round's penalty shootout win over Copenhagen, again rescued Red Star when he tipped over a stoppage-time piledriver by Jean Pierre Nsame.
The final whistle from English referee Anthony Taylor sparked wild celebrations among the jubilant Red Star fans, who lit flares after parking a fully decommissioned battle tank in front of the stadium on Monday.
Dinamo fell behind on the night to an early Babajide David goal before Amer Gojak struck in the 71st minute to put the tie beyond Norwegian side Rosenberg's reach.
Olympiakos arrived in Krasnodar with a 4-0 first-leg cushion and although the Russian side gave themselves a glimmer of hope through Daniil Utkin's 10th-minute effort, Youssef El Aarabi scored twice for the visitors to book their group-stage berth.
Last season's semi-finalists Ajax Amsterdam are at home to APOEL Nicosia in Wednesday's standout fixture following a 0-0 first-leg draw in Cyprus.
Bruges are at home to LASK Linz following a 1-0 win in Austria and Slavia Prague host Romanians CFR Cluj after beating them by the same score last week.