Portsmouth were caught cold in Braga tonight by Luis Aguiar's brilliant free-kick and never recovered, getting their Group E campaign off to the worst possible start.
Harry Redknapp's men offered very little and when Wason Renteria doubled the hosts' lead after the break it was all over for.
When Armand Traore fired Pompey's opening salvo from a Jermain Defoe pass it led to a corner which Braga keeper Eduardo struggled to clear. But in the eighth minute the visitors were stunned when Aguiar curled in the opening goal from a superb 30-yard free-kick after a foul by Papa Bouba Diop on Vandinho.
Pompey looked desperate when Braga grabbed a second goal a minute after the break. It was cleverly set up by Meyong's step-over dummy, Luis Aguiar's through-pass and then Renteria's well-timed run, the striker finishing with style.
Pompey had the ball in the net just before the hour-mark, Crouch's header appearing to go in off defender Evra's body but the referee ruled it out. Redknapp's misery was complete when Alan added a late third.
Braga: Eduardo, Frechaut, Moises, Alberto Rodriguez, Evaldo,
Vandinho, Alan, Matheus, Aguiar, Renteria, Meyong. Subs: Mario Felgueiras, Mossoro, Paulo Cesar, Jorginho, Stelvio Cruz, Cesar Peixoto, Joao Pereira.
Portsmouth: James, Campbell, Pamarot, Armand Traore, Distin, Davis, Diop, Hreidarsson, Little, Defoe, Crouch. Subs: Ashdown, Utaka, Mvuemba, Hughes, Kanu, Belhadj, Wilson.
Referee: Darko Ceferin (Slovenia)