Atletico Madrid obliterated Udinese's unbeaten Europa League record with an emphatic Group I victory in Spain.
Udinese arrived at the Vincente Calderon in confident mood, knowing a win would have seen them reach the last 32.
Yet they found themselves 3-0 down by half-time as Adrian Lopez struck twice and Diego added a third, before Radamel Falcao Garcia rounded off a good night for the Spanish outfit after the break.
A 2-0 home victory over Atletico a fortnight ago saw Francesco Guidolin's side go three points clear of the Spanish outfit at the top of the standings.
Victory tonight would have assured the Italians of at least second place in the final standings but, instead, Atletico won to boost their hopes of edging Celtic and Rennes in the battle to progress.
Atletico were quickly out of the traps as Falcao forced Samir Handanovic to parry his 20-yard shot away.
Barely a minute later the hosts were in front, as Arda Turan played the ball in from the right and Adrian turned it home low into the right-hand corner.
Udinese were stunned again in the 12th minute as the same player made it 2-0.
This time full-back Antonio Lopez was the creator, crossing accurately from the right for Adrian to ghost in and nod home.
The Italians finally stirred as Diego Fabbrini's shot was saved by Thibaut Courtois before going off injured.
Udinese forward Antonio Floro Flores shot wide from the edge of the box
It was 3-0 by the break as playmaker Diego found a yard of space to slot home Adrian's slick pass from the left and delight the partisan Vicente Calderon crowd.
Turan sent a shot whizzing over as the second half creaked into life.
At the other end Almen Abdi had Udinese's best chance as his effort from distance crashed against the bar, before Falcao got in on the goalscoring action with the fourth, the Colombian smashing home as Udinese failed to clear in the box.
Koke had a chance for Atletico but shot wide before Falcao forced Handanovic into a decent save from his close-range stab at goal.
