The La Liga champions looked on course to reach the Madrid final after goals from Luis Suarez and Lionel Messi sealed a 3-0 home victory at Camp Nou last week.
Liverpool FC were without Mohamed Salah and Roberto Firmino for the second leg, which only made the home side’s task even harder against their fellow five-time winners.
However, the Reds started an incredible comeback when Divock Origi broke the deadlock in the seventh minute with a close-range finish.
Georginio Wijnaldum was introduced from the bench at half-time and the Dutch midfielder scored two quick goals to level the tie on aggregate.
Liverpool FC’s memorable European night was complete when Origi scored a winner with 11 minutes to go following Trent Alexander-Arnold’s quick corner.
The Reds will be looking to win the Champions League for the sixth time after Klopp’s men lost 3-1 to Real Madrid last term.
And FC Barcelona took to Twitter to send a message to the Premier League side following their 4-3 aggregate loss.
The Spanish club wrote on the social media website: “Congratulations”.
— FC Barcelona (@FCBarcelona) May 7, 2019
Liverpool FC haven’t won the Champions League since the Reds beat AC Milan on penalties in 2005.
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