England vs. Iran (Monday, 1.00pm)
England and Manchester City right-back Kyle Walker has already admitted that Monday's game will come too soon for him as he battles back from groin surgery, while James Maddison missed training earlier this week to manage his workload following an injury scare last weekend and is also set to miss out.
The Leicester City man was never expected to feature from the first whistle here, though, and Kieran Trippier should be given the nod on the right in Walker's absence, while the age-old question of whether Southgate will line up with a back three or back four is already being asked.
Rice and Kalvin Phillips formed an effective midfield partnership at Euro 2020, but the latter's lack of game time following shoulder surgery could tempt Southgate into selecting fan favourite Jude Bellingham for the opening matchday.
As for Iran, experienced midfielder Omid Ebrahimi is the most notable absentee from their squad due to a groin injury, but Bayer Leverkusen striker Sardar Azmoun is part of the team despite tearing a calf muscle last month.
It would be a shock to see Azmoun considered for a start here, but Queiroz has another established centre-forward in Porto's Mehdi Taremi ready to shoulder the goalscoring burden, and he should be supported by a familiar name in Alireza Jahanbakhsh.
Ehsan Hajsafi will wear the captain's armband as he prepares to make his 122nd appearance for Team Melli, while Brentford's Saman Ghoddos should be content with a place on the bench.
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> How Iran could line up against England
> How England could line up against Iran
> England vs. Iran: How do both squads compare ahead of World Cup Group B clash?
> What should England's starting XI be for their World Cup opener?
Senegal vs. Netherlands (Monday, 4.00pm)
Mane has withdrawn from the Senegal squad as a result of his fibula injury, which will require surgery, with the likes of Nicolas Jackson, Iliman Ndiaye, Krepin Diatta and Bamba Dieng all fighting for a spot on the left flank in his absence.
Diatta could win that particular battle due to his natural pace and trickery on the ball, while RB Leipzig's Abdou Diallo may miss out on his country's first match at the World Cup with a knee issue.
Netherlands, meanwhile, will be without their own attacking talisman, too, with Memphis Depay ruled out of at least their opening match due to a hamstring injury. The Barcelona forward, who scored 12 goals during World Cup qualifying, has not played for club or country since sustaining against Poland in September.
Denzel Dumfries is also doubtful after being forced off during Inter Milan's Serie A fixture against Atalanta last week, with Marten de Roon unlikely to be available either having missed that match entirely with a back issue.
As such, Jeremie Frimpong and Vincent Janssen may be handed opportunities from the start, although van Gaal could utilise three central midfielders with Cody Gakpo and Steven Bergwijn forming a front two.
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> How Senegal could line up against Netherlands
> How Netherlands could line up against Senegal
USA vs. Wales (Monday, 7.00pm)
Zack Steffen was expected to wear the gloves for the United States in Qatar, but an uninspiring season with Manchester City, which saw him replaced by Stefan Ortega as backup, has led to him losing his place in the squad altogether.
Matt Turner and Ethan Horvath are the two men set to battle it out to start in goal, and Arsenal man Turner played in both September friendlies so may have the upper hand.
Weston McKennie has not featured for Juventus since October, but he should be fit in time to feature from the start in midfield here.
The main strength for the US comes in the attacking third, with many options available to Berhalter, meaning one or two may be unfortunate to miss out, as Timothy Weah, Gio Reyna and Jesus Ferreira are all staking a claim to start in attack alongside Christian Pulisic.
Gareth Bale revealed earlier in the week that he is ready and prepared to play 90 minutes in all three of Wales's group games if necessary, despite him being reduced to mainly cameo appearances since joining LAFC in MLS this year.
Joe Allen has been out injured since late September, but he believes he will be ready to take part in this group opener.
However, defender Rhys Norrington-Davies has not been as fortunate, as the Sheffield United man will not play any part in the tournament for Wales, following his injury against Coventry City last month.
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> How Wales could line up against USA
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