Brazil will be seen in action at a time when upsets are in vogue, with both Argentina and Germany losing 2-1 to Saudi Arabia and Japan in the past two matchdays.
On a fifth day today, the first kick-off features Xhaka-led Switzerland facing off five-time AFCON winners Cameroon at 3.30 p.m.
The Europeans feature a new coach and remain unbeaten in World Cup qualifying.
The Cameroonians, on the other hand, come into the tournament as the fourth-lowest-ranked side.
The second game of the day could prove to be another surprise result, with South Korea confirming that Manchester City midfielder Heung-min Son is fit to play against Uruguay at 6.30 PM today.
The South Americans come into the game shrouded in uncertainty, with new coach Diego Alonso who took over at the end of 2021.
Cristiano Ronaldo-led EURO winners Portugal will take on four-time AFCON champions Ghana at 9.30 pm. Ghana made its way back to World Cup, having been absent for the 2018 edition.
This is their fourth World Cup appearance since 2006. While, Cristiano Ronaldo will participate in his fifth and, probably, final World Cup with Portugal in this Group H match.
The match takes place after the cancellation of Ronaldo's contract by Manchester United.
Brazil will take on Serbia at 12.30 a.m. when South Americans are tipped to be favourites to win the tournament this year. Their first test comes in the form of a dark horse Serbian team who topped their group in qualifying, beating EURO winners Portugal 2-1.