Villarreal's fairytale debut in the Champions League continued when a 1-0 victory over Italian giants Inter Milan sent them into the semi-finals on the away goals rule.
Argentine defender Rodolfo Arruabarrena levelled the aggregate score at 2-2 when he headed compatriot Juan Roman Riquelme's clipped free kick over Inter keeper Francesco Toldo 13 minutes into the second half.
The Primera Liga side, whose first taste of European football came just four years ago when they played in the Intertoto Cup, will meet Arsenal or Juventus in the semi-finals.
The Spaniards controlled the game for long periods with their trademark brand of patient possession football but scoring chances were at a premium in a tight, tactical game.
It was not until the outstanding Riquelme earned his side a free kick after he had been brought down by Luis Figo that the Spaniards were given the chance to claim their historic victory.
The win sparked wild scenes in the Madrigal stadium, where the vast majority of the 22,000 fans cheered the home team's lap of honour.
Villarreal made an ambitious start following their 2-1 defeat in last week's first leg at the San Siro.
Roared on by the capacity crowd, Villarreal shifted up a gear midway through the half and put the Italians under heavy pressure, pinning them back for a lengthy spell midway through the half.
Midfielder Marcos Senna went close with two fierce drives and Juan Pablo Sorin tested the Inter centre-backs as he piled forward to join the attack.
Riquelme then took centre stage as he stepped up to run the show in midfield. He gave Toldo a scare with a dipping shot over the bar after he had teased his way past the Inter back four.
Moments later former Juventus player Alessio Tacchinardi went even closer when he headed just wide of the near post from a corner, but Inter held firm to keep the Spaniards at bay.
Inter had just one shot on goal in the first half when Dejan Stankovic tried a long-range effort that swirled over the bar.
Villarreal started the second half as they had ended the first and they were only denied the lead when Toldo tipped a goalbound shot from Jose Mari over the bar.
It was Riquelme, though, who was the architect of Villarreal's famous victory.
Brought down by Figo as he surged towards the area, he then delivered a teasing free kick that the rising Arruabarrena glanced over Toldo and into the net.
The Spaniards almost extended their lead moments later when Diego Forlan sent a curling strike towards the top corner only to see Toldo pull off a brilliant one-handed save.
Villarreal had a strong case for a penalty when Marco Materazzi elbowed Sorin in the face as he ran towards a free kick in the area, but the incident went unpunished.
With Riquelme continuing to boss the midfield, Villarreal remained in charge for the remainder of the game.
Forlan drilled wide in the 82nd minute and Riquelme forced a brilliant save from Toldo with a wickedly swerving drive from wide out on the right.
