With a clear disparity in strength between teams on opposite sides of the draw, winning the group might not be all it's cracked up to be.
Belgium boss Martinez said the England game was an opportunity to "refresh" his starting line-up with his side also safely through.
"I think the level of the game will be high, higher than perhaps if there are no changes given that both teams are through", he said.
"We have qualified and that was the priority", Martínez told the media. If you do not play to win, you are cheating your opponents, deceiving those who are watching, and also fooling yourself.
"We want to breed a mentality that everybody in our squad wants to constantly win".
Now the Three Lions are ahead of Belgium on the table thanks to the fact that the Red Devils have accrued three yellow cards to England's two. It states: "Winning is the object of playing any game".
Do you keep a winning team together to maintain momentum?
However, with passage to the round of 16 alongside Belgium already guaranteed, Southgate has to decide what changes to make to his XI in an effort to rest some player and give others from the bench a chance.
Japan upsets Colombia, 2-1
The 2018 World Cup has already been a memorable one with two records being thrashed in both good and bad ways. Japan will take on Senegal on June 24 and then face Poland on June 28.
"We want to win the game", said Southgate.
As one can see, the group toppers will move into the top half of the draw while the group runners-up move into the bottom half of the draw.
"You are thinking quarter-final, semi-final and I think that someone, including England, is going to have a huge opportunity".
Whether Southgate's comments are just lip service or a statement of intent remains to be seen.
England's manager is wary of his memories of the 2002 World Cup when he did not play a single minute and, while he wished his team-mates well, ultimately found it a frustrating time.
Marcus Rashford could also come in for Raheem Sterling, who has underperformed so far in Russian Federation.
This added individual wrinkle - along with the players' natural competitiveness - will certainly effect how both sides approach tomorrow's match.