Liverpool will play Sevilla in the Europa League final later this month after comfortably beating Villarreal 3-1 on aggregate.
Dejan Lovren’s header was then saved by Areola as the Reds continued to dominate a match that grew increasingly bad-tempered as the first half drew to a close.
At the start of the second half Lovren did well to get in a last-ditch challenge to deny Cedric Bakambu as the Yellow Submarine tried to catch their hosts out.
Philippe Coutinho then saw his shot saved by Areola before Milner was also denied by the Villarreal keeper.
Unmarked former Tottenham striker Roberto Soldado headed wide for the visitors in the 55th minute before Daniel Sturridge launched a rapid counter-attack only to see Areola keep his rasping effort out.
Sturridge did score in the 63rd minute though after being set up by Firmino, his effort hitting both posts before nestling in the back of the net.
Villarreal had Victor Ruiz sent off in the 71st-minute after picking up two yellow cards and Lallana sealed Liverpool’s place in the final with a third goal nine minutes from time.
The Reds made the best possible start to the semi-final second leg at Anfield after losing 1-0 in Spain last week.
After Mario Gaspar had shot straight at Simon Mignolet, Liverpool took the lead in the seventh minute when Nathaniel Clyne’s cross was parried by Alphonse Areola to Roberto Firmino, who sent the ball back into the danger area where it went into the net off Bruno Soriano.
Liverpool continued to pour forward and James Milner set up Adam Lallana, whose first-time effort drifted wide.
Villarreal slowly started to work their way back into the match and Jonathan dos Santos played in Gaspar midway through the first half, but his tame effort was gathered by Mignolet.