Liverpool defender Trent Alexander-Arnold admitted Villarreal made life “really difficult” as Jurgen Klopp’s side battled through to a third Champions League final in five years on Tuesday.
The Reds led 2-0 from last week’s semi-final first leg at Anfield, but first-half goals in Spain from Boulaye Dia and Francis Coquelin levelled the tie on aggregate.
A much improved Liverpool regained control in the second half at La Ceramica where goals from Fabinho, Luis Diaz and Sadio Mane gave them a 3-2 win on the night and a 5-2 aggregate victory.
“We never seem to make these Champions League semi-finals easy for ourselves. Difficult, really difficult,” Alexander-Arnold told BT Sport.
“We came here and they played very well first half. We regrouped at half-time and got the game by the scruff of the neck. We did what we needed to do.”
Liverpool are bidding for an unprecedented quadruple, but looked in danger of losing a match by two goals for the first time this season after an uncharacteristic opening 45 minutes.
“We never played football that first half and didn’t pick up any second balls. They played the game they wanted to and we allowed them to do that,” said Alexander-Arnold.
“Second half we came out and controlled the ball better. One bad half over two legs, we can concede that to get the job done.”
Six-time European champions Liverpool will play Premier League rivals Manchester City or Real Madrid in the final in Paris on May 28.