Celtic's UEFA Cup flame finally flickered out after their defence and attack failed to shine in the El Madrigal Stadium on Wednesday night.

Sonny Anderson and Roger Garcia capitalised on some sloppy play in the Hoops backline by Bobo Balde and Joos Valgaeren in each half to guide Villarreal into the last four.

Celtic's chances were hit before kick-off when Chris Sutton failed to recover from a groin injury. The Hoops were already weakened by the suspension of Alan Thompson.

O'Neill was forced to name a defensive side with Jackie McNamara shaking off a hamstring injury to come in along with Manchester United-bound Liam Miller.

But even with the backline enhanced there were huge gaps which were exploited by Villarreal.

Celtic made the worst possible start as they fell behind after just six minutes.

Juliano Belletti hung the ball in the air from the right and Anderson reacted to hesitancy from Balde to head the ball over an exposed David Marshall from just inside the box.

Balde was having a shocker and was lucky to escape another moment of weakness in the 13th minute.

Mari was able to take the ball down and burst into the box, with Balde failing to put in a decent challenge, but his stretching leg could only fire over the crossbar from 14 yards.

The Celtic defence were fast asleep in the 19th minute as Riquelme was able to fire a shot, from just outside the box, wide.

With Larsson alone in attack they struggled to cause Villarreal's defence any bother and their wall comfortably coped with Stanislav Varga's shot after 23 minutes.

Celtic came back into it after that but Miller was unable to keep a hopeful right-foot swipe down after Henrik Larsson had picked him out in the box.

Celtic had good claims for a penalty on the half-hour as McNamara seemed to get tripped in the box by Rodolfo Arruabarrena in the box.

There were encouraging signs for Celtic as Anderson deflected Stilian Petrov's free-kick wide before squandering a glorious chance to go level in the 32nd minute.

McNamara swung an inviting cross into the box and Stephen Pearson came in and jumped high over the Villarreal defence but headed over from just eight yards.

Valgaeren could have gone some way to saving Balde's blushes when he was put through by Petrov. The Belgian was still faced with a difficult angle but he got a shot away which was well blocked by goalkeeper Jose Reina.

At the other end Celtic continued to look vulnerable and Anderson should have at least tested Marshall from six yards but headed well wide in the 43rd minute.

Celtic stepped up the tempo after the break but the Villarreal defence were stronger than the visiting backline.

They did look vulnerable though in the 55th minute when Larsson got on the end of Didier Agathe's cross to head wide with Valgaeren just unable to steer the ball home.

Mari could have put the game out of Celtic's reach in the 58th minute but he wildly slashed his effort over.

Balde made amends for his early low point, moments later, when a crucial last-ditch tackle in the box blocked Anderson's strike.

Miller could have equalised in the 62nd minute when Lennon's free-kick hit Varga and landed at his feet but he blazed his left-foot shot high and wide.

Celtic's mission became impossible in the 68th minute when Villarreal increased their advantage.

Anderson was the provider as he crossed from the left and Garcia showed more desire than Valgaeren and blasted the ball past Marshall.

O'Neill made a double substitution in the 70th minute with Jamie Smith and Ross Wallace replacing Miller and Pearson.

Sebastian Battaglia became the next man booked for a foul on Petrov before Larsson fired the free-kick high over which summed up Celtic's gloomy night.

Teams

Villarreal: Reina, Arruabarrena, Coloccini, Belletti, Ballesteros, Josico, Roger, Battaglia, Riquelme, Jose Mari (Javi Venta 85), Anderson.

Subs Not Used: Lopez Vallejo, Marti, Victor, Guayre, Quique Alvarez, Calleja.

Booked: Josico, Battaglia, Arruabarrena, Javi Venta.

Goals: Anderson 6, Roger 68.

Celtic: Marshall, McNamara, Valgaeren, Balde, Varga, Agathe, Lennon, Miller (Smith 71), Petrov, Larsson, Pearson (Wallace 71).

Subs Not Used: Douglas, Sylla, Lambert, Mjallby, Beattie.

Booked: Valgaeren, Pearson. Agg (3-1)

Att: 15,964

Ref: Massimo De Santis (Italy).