Liverpool crashed out of the Europa League after a 1-0 win against Atalanta that wasn't enough to overturn their quarter-final deficit, while Bayer Leverkusen's 1-1 draw at West Ham took the German champions into the last four on Thursday.
In Jurgen Klopp's last season as Liverpool boss, the Reds were hoping to give the German a memorable farewell in the final in Dublin.
But Liverpool had suffered a stunning 3-0 loss in the first leg against Atalanta at Anfield last week.
And although Liverpool have authored some of European football's greatest comebacks down the years against the likes of St Etienne, AC Milan and Barcelona, there would be no miracle escape this time.
Mohamed Salah converted a seventh minute penalty in the second leg in Bergamo after Trent Alexander-Arnold's cross hit Matteo Ruggeri's arm.
However, Klopp's men couldn't breach the stubborn Atalanta defence again.
It has been a brutal week for Liverpool, whose Premier League title challenge was damaged by a shock home defeat against Crystal Palace on Sunday.
"It's mixed emotions. We are out but I'm happy with the game," Klopp said.
"It was clear we gave ourselves a massive hurdle. We wished we could have gone to Dublin but that hasn't happened."
While Klopp contemplates his failure to land the one major trophy to elude him during nine years with Liverpool, Atalanta can dream of winning the second silverware in their 116-year history after the 1963 Coppa Italia.
Bidding to reach their maiden European final, Gian Piero Gasperini's team will face Marseille in their first European semi-final since the 1988 Cup Winners' Cup.
Fresh from clinching their first Bundesliga title last weekend, Leverkusen survived a scare from West Ham before advancing 3-1 on aggregate.
In the semi-finals, Xabi Alonso's side will play Roma, who saw off Italian rivals AC Milan 3-1 on aggregate.
Leverkusen won the first leg 2-0 but West Ham made the perfect start in east London when Michail Antonio met Jarrod Bowen's pin-point cross with a close-range header in the 13th minute.
West Ham eventually ran out of steam and Jeremie Frimpong struck in the 89th minute with a shot that deflected in off Aaron Cresswell.
"The momentum was with West Ham. To be honest, we were not at our best in the first half. I'm happy to go through. In the Europa League you always have tough moments," Alonso said.
Leverkusen are into their second successive Europa League semi-final, while West Ham's exit means for only the third time in the 21st century, England will have no teams in the Champions League and Europa League last four.
Leverkusen's 44-game unbeaten run in all competitions has taken them to the brink of an incredible treble, finally ridding the club of the 'Neverkusen' tag that mocked their decades of underachievement.
Alonso's team, who face second tier Kaiserslautern in the German Cup final on May 25, beat Werder Bremen 5-0 on Sunday to win the Bundesliga title.
At the Stadio Olimpico, Gianluca Mancini put Roma head from close-range in the 12th minute and Paulo Dybala doubled their advantage in the 22nd minute with a blistering strike.
Daniele De Rossi's side were reduced to 10 men in the 31st minute when Zeki Celik was dismissed for a foul on Milan forward Rafael Leao.
Matteo Gabbia got one back in the 85th minute, but his header was little consolation for Milan.
After losing last season's Europa League final against Sevilla, Roma are one step closer to finally winning the competition for the first time.
Roma, who won the Europa Conference League in 2022, are into their fifth European semi-final in the last seven seasons.
In the south of France, Marseille were 4-2 winners in a penalty shoot-out against Benfica following the French side's 1-0 victory in a tie that finished 2-2 on aggregate.
Faris Moumbagna struck in the 79th minute, heading in Pierre-Emerick Aubameyang's cross to force extra-time.
In the shoot-out, Luis Henrique scored the winner for Jean-Louis Gasset's side after Benfica duo Angel Di Maria and Antonio Silva missed their kicks.
