Qatar crashed to a 2-0 defeat against Ecuador from Enner Valencia's brace on Sunday and with it became the first host nation to lose an opening match at a World Cup tournament.
Striker Valencia had a third-minute effort disallowed for offside in the build-up but then converted a penalty in the 16th and headed the second in the 31st minute of a lopsided affair.
Valencia is Ecuador's only World Cup scorer as he also netted all of their three goals at the nation's debut in 2014.
Harmless World Cup novices Qatar face a big challenge to survive the first round, with their other Group A games Friday against African champions Senegal and November 29 against the Netherlands.
South Africa in 2010 are the only previous hosts to be knocked out in the first stage.
The opening match at Al Bayt Stadium in Al Khor set off the first World Cup during the European winter and in the Arab world, after a difficult build-up with with lots of criticism on Qatar's human rights record.
