The first World Cup to be held in the Arab world will kick off on Sunday when the host nation, Qatar, faces Ecuador.
After a last weekend of action, domestic football leagues paused for six weeks for the global showpiece - but preparation time is short for the teams.
Two of Europe's big guns, England and the Netherlands, are among the teams due to arrive on Tuesday.
As teams rushed to submit their final squad lists, Iran named Sardar Azmoun, their star player who has expressed support for the demonstrations in his homeland, in their final squad.
Azmoun, who plays for German club Bayer Leverkusen, has posted several social media messages in support of the protests that were sparked by the death of 22-year-old Mahsa Amini.
Activists have called on fans attending Iran's matches in Qatar to chant Amini's name.
Holding football's showpiece event in a desert state has necessitated an unprecedented reorganization of the international football calendar, shifting the World Cup from its normal slot in the northern hemisphere summer to avoid the Gulf's scorching heat.
Sunday's kickoff marks the culmination of Qatar's extraordinary campaign first to win the vote to land the tournament and then embark on a spending spree of tens of billions of dollars to build stadiums and infrastructure.
World governing body FIFA's pleas to "focus on the football" have struggled to be heard as the countdown to kick-off has only increased scrutiny of the country's treatment of migrant workers, women and the LGBTQ community.
Labourers from South Asia have been at the centre of an often acrimonious dispute over deaths, injuries and working conditions since Qatar was awarded the World Cup in 2010.
Amnesty International has urged FIFA to commit to compensating migrant workers "for abuses suffered" during preparations for the tournament.
Qatar has angrily rebuffed most of the attacks and local media have blasted the "arrogance" of some Western countries.
Organizers have predicted more than one million fans will travel to Qatar.
Tournament chiefs say that 2.9 million of the 3.1 million tickets have been sold, with fans waiting outside ticketing centers in hopes of seeing top games.
Qatar announced its first arrests of World Cup ticket touts on Monday, with three foreign men detained outside official ticketing sites in Doha. No details were given of their nationality.