DOHA, Qatar -- As far as opening tests go, they do not come much tougher than what Saudi Arabia have awaiting them.
And not just any old Messi. One that -- in his World Cup swansong -- will be determined, along with his teammates, to go all the way and win the one trophy missing from his cabinet -- and the biggest one of all.
Saudi Arabia do not have to think too far back for a reminder of how a World Cup campaign can rapidly nosedive from a heavy opening defeat.
Just four years ago at Russia 2018, the Green Falcons featured in the curtain raiser and were duly thumped 5-0 by the hosts.
They were never able to recover despite restoring some pride in their second match as a creditable 1-0 loss to Uruguay confirmed their elimination, although they did finish on a high by bowing out with a come-from-behind win over Egypt.
Argentina is an entirely different proposition altogether.
And Saudi Arabia do not have any players that come close to having the experience of regularly testing themselves against top-level opponents that Argentina will pose -- given none of Herve Renard's squad ply their trade outside the domestic Saudi Professional League.
They can take heart from the fact that they did nullify a certain Mohamed Salah from four years ago in their victory over Egypt.
Mohammed al-Breik and Yasser al-Shahrani -- the two fullbacks from that day -- remain seasoned campaigners of the current Saudi Arabia side. On occasions where Salah drifted out wide, they did an excellent job curtailing his influence.
Nonetheless, both centre-backs that can take credit from that victory -- Osama Hawsawi and Motaz Hawsawi -- have both since retired. It will now be up to the next generation -- potentially the likes of Abdulelah al-Amri and Hassan Tambakti -- to step up to the task.
There is also the fact of the matter that, in that win over Egypt, Saudi Arabia were largely able to focus most of their attention on the Liverpool man -- with all due respect to his international teammates.
With all that said, there is perhaps never going to be a way to stop a quality team with an individual talent as gifted as one who is arguably the greatest of all time. Even top international sides have been torn apart by Messi in the past -- there will be no shame if Saudi Arabia suffer a similar fate.
But they must at least try to keep Argentina at bay as much as they can, and it will require a team effort to do just that.
And they will at least look to those games knowing they no longer have to come up against one of the greatest of all time after Tuesday.