Half-time substitute Joseba Llorente bagged a hat-trick as Villarreal survived a real scare before turning on the style in their Champions League clash with AaB.

Llorente replaced the ineffective Guillermo Franco at the interval and scored twice inside three minutes to give the hosts what proved an unassailable 4-2 lead.

Villarreal had not conceded two goals in a game all season going into the clash, but did so inside the opening 45 minutes here.

Marek Saganowski gave the Danes a deserved lead and Thomas Enevoldsen brought them level after Giuseppe Rossi and Joan Capdevila had struck for the Yellow Submarine.

AaB were eventually overwhelmed after the break, despite a third goal from Andreas Johansson which made it 4-3, as further efforts from Robert Pires and Llorente sealed the win for Villarreal.

All five second-half goals came in a stunning 17-minute spell.

The win moves the Primera Liga side on to seven points from their opening three games in Group E, level with Manchester United, while AaB remain on one.

Villarreal may be lying third and AaB second bottom in their respective domestic leagues, but for the opening 15 minutes the Danes looked for all the world like the form team.

Only some wayward finishing prevented them from being a couple of goals up before the hosts had even mounted a meaningful attack.

Anders Due broke down the left early on before pulling a tame shot well wide of the far post, while Johansson found space 25 yards out only to slice his right-footed shot horribly off target.

Saganowski was then played in by Johansson but, stretching for the ball, could only lift his shot over the bar.

But the Poland international made no mistake in the 19th minute when he was left completely unmarked from Due's left-wing cross and planted a diving header past Diego Lopez.

That goal seemed to stir Villarreal into action and their first effort on goal - in the 28th minute - brought them level.

Santi Cazorla's ball inside the left-back sent Angel Lopez down the right and his low cutback found Rossi, whose side-footed finish was deflected past Karim Zaza.

If that goal came courtesy of a neat team move the strike which gave them a 33rd-minute lead was all Capdevila.

The defender controlled a dropping ball on the edge of the area with his left foot and with his next touch cracked a swerving right-footed shot which flew into the far top corner.

But the Yellow Submarine were rocking again just three minutes later.

Two defenders came out to close down Saganowski, but it was the striker who got his foot to the ball, flicking it on for Enevoldsen to run on to and - with the centre backs nowhere to be seen - clip the ball home.

Villarreal were almost back in front within seconds of the restart after some quick feet from Rossi gave him a shooting chance and his effort stung keeper Zaza's palms.

The stopper was culpable when the Spaniards went back in front in the 67th minute, though.

Marcos Senna's long-range shot bounced awkwardly in front of him but he should still have collected in cleanly.

Instead the ball came back off his chest and Llorente following in scrambled home the loose ball at the second attempt.

And he added a second three minutes later with another tap in, fellow sub Pires picking him out at the far post with a low cross after the Frenchman had shaken off a defender and broken down the right.

AaB though would just not lie down and Johansson made it 4-3 when he powered home a header in the 77th minute.

Two minutes later Pires nodded in the rebound after Zaza had parried Cazorla's shot out into the six-yard box and Llorente made it six in the 84th minute with a sidefoot volley to convert Capdevila's cross from the left.