Liverpool beat Chelsea 4-1 on penalties to reach the Champions League final for the second time in three seasons after a night of unrelenting tension at Anfield on Tuesday.

The second leg ended 1-0 after extra time with the only goal coming from Liverpool's Danish defender Daniel Agger in the 22nd minute.

Liverpool's Pepe Reina celebrates after their Champions League semi-final, second leg soccer match against Chelsea in Liverpool May 1, 2007.[Reuters]

With the tie locked in a 1-1 stalemate after Chelsea's 1-0 win at Stamford Bridge last week, the stage was set for the first penalty shootout at the semi-final stage since the Champions League replaced the old European Cup in 1992.

Liverpool won it -- their 10th victory in 11 shootouts in various competitions down the years -- to eliminate Chelsea at this stage for the second time in three seasons.

Liverpool manager Rafael Benitez paid tribute to the Anfield crowd.

"I think they knew today how to beat Chelsea -- to play with passion," Benitez told a news conference.

"Hearing your supporters behind you as today, I felt they played with determination, with passion and with heart... I'm really proud of my players."

The only goal of a nerve-wracking 120 minutes came following a cleverly-taken free kick from Liverpool captain Steven Gerrard, who sent a low cross towards the edge of the Chelsea penalty area rather than the expected high ball to the middle.

Agger played his part perfectly, sweeping in a well-struck shot that swerved just inside the post and out of the reach of goalkeeper Petr Cech.

It was Chelsea's first defeat in 24 matches since losing to Liverpool in the Premier League in January.

"There is little to say. This is a moment where everyone has to be strong," Chelsea manager Jose Mourinho said. "The players have a lot of reasons to be proud of themselves.

"We were the best team today, even against a team playing only in the Champions League. Football is like this, we have to be strong to face it."

ALL SCORED

Boudewijn Zenden, Xabi Alonso, Gerrard and Dirk Kuyt converted penalties for Liverpool, while goalkeeper Pepe Reina saved efforts by Chelsea's Arjen Robben and Geremi to send Liverpool through to their seventh European Cup final. They will play Manchester United or AC Milan in Athens on May 23.

Chances were few and far between with Peter Crouch having a header saved by Cech's feet on the line after 55 minutes and Kuyt heading against the Chelsea bar just before the hour.

At the other end, Didier Drogba drew a fine save from Reina after 32 minutes and Dutch striker Kuyt had an effort ruled out for offside in extra time.

PREFERRED ROLE

Liverpool took the game to Chelsea from the start and made good use of Crouch's height before scoring from their first chance.

Joe Cole conceded a free kick on the left and Gerrard squared it low for Agger to provide a clinical finish.

The goal, which looked as if it had come straight from the training pitch, roused Chelsea from their lethargy and it took a good block by Reina to stop Drogba's angled shot on the run after 32 minutes.

Michael Essien might also have grabbed an equaliser, but the Ghanaian midfielder-turned-defender's effort drifted wide of the target after a nod-on by Drogba.

Kuyt was no luckier a few minutes later when he sent a header past Cech, only to see the ball strike the crossbar and bounce to safety.

The Anfield crowd, which had been belting out its passionate support since kickoff, made sure the atmosphere stayed electric as Liverpool turned the screw on the visitors who seemed more intent on not conceding than trying to score.

Liverpool always looked the hungrier side, underlined by Zenden's fierce 25-metre shot from the left flank which Cech only gathered at the second attempt, but there were no further goals.