Matias Nicolas Garcia's early strike condemned 10-man Linfield to a disappointing 1-0 defeat by Maltese side Floriana in the Europa League qualifier.
Garcia's shot deflected off Ross Larkin and flew into the bottom corner after nine minutes at Windsor Park.
A sluggish and disjointed Linfield side failed to mount a sustained response but they improved in the second half.
Floriana keeper Ini Akpan made two superb saves while Larkin was sent-off for two yellows with 16 minutes left.
David Healy's side impressed despite losing 1-0 to Legia Warsaw in last month's Champions League qualifier but this was a largely tepid display against a resolute Floriana side.
The Maltese champions, who won their national title for the first time in 27 years last season, chalked up just a fifth win in 66 European games thanks mainly to an excellent opening in Belfast.
Threat on the counter
Garcia's goal capped a confident start and Floriana continued to threaten on the counter-attack as Linfield mustered just one shot on target in the first half.
That came 44 minutes in with midfielder Bastien Hery sending his powerful effort straight at Akpan.
Linfield upped the pace on the restart and Akpan produced a great block to deny Stephen Fallon before Hery hooked wide from the follow-up.
Floriana now posed only an occasional threat - Venancio fizzed just wide - but they remained organised and firm in defence as the Blues began pushing for an equaliser.
Linfield substitute Andrew Waterworth came close to scoring with his first touch of the game as the striker swivelled and fired over.
Larkin had no complaints for his dismissal on 74 minutes, with his high challenge bringing down Uli Arias as he tried to cover for a mistake by team-mate Ethan Boyle.
Akpan again came to Floriana's rescue in injury time with a wonderful reflex save from Jimmy Callacher's header before Christopher Maginza volleyed wide with Linfield's final chance.
Floriana's reward is a home third-round qualifier against Estonia's Flora Tallinn next Thursday.
- 3LarkinBooked at 74mins
- 15NasseriSubstituted forManzingaat 61'minutes
- 16ClarkeBooked at 29minsSubstituted forWaterworthat 62'minutes
- 6CallacherBooked at 72mins
- 14LaveryBooked at 51mins
- 20FallonBooked at 20mins
- 21HérySubstituted forKearnsat 78'minutes
- 7Venancio da SilvaBooked at 65mins
- 8LeoneBooked at 68mins
- 9KeqiSubstituted fordos Santos da Silva Cheveresanat 83'minutes
- 20GarciaBooked at 59mins
- 11PaiberSubstituted forAriasat 61'minutesSubstituted forBeyeat 86'minutes
- 27dos Santos da Silva Cheveresan
- David Munro