The goal also ensured that Belgium topped the group and booked a last-16 clash with Japan in Rostov, consigning England to a match-up with Colombia in Moscow and a much less formidable opponent in the quarters in Switzerland or Sweden if they make it past the South Americans.
But Southgate feels the fact his country last won outside of the group stages at a major tournament in 2006 should override any plotting on the behalf of his youthful and in-form side. You don't want to see smiles in the changing rooms.
Reigning champions Germany labouring to an early exit and Argentina scraping second in Group D behind Croatia means the runners-up in England and Belgium's section could have a more comfortable run of games on paper.
For those of you concerned that neither England nor Belgium would want to win, you will be delighted to find out that's exactly how it panned out.
How both sides approach the match will be a good indicator of their respective philosophies and team culture.
Since winning the World Cup in 1966, England have won just SIX games in knockout worldwide football.
In a timid first-half, yellow-cards for Youri Tielemans and Leander Dendoncker were greeted with an unusual sense of excitement. The "Red Devils" were behind on fair play points and a couple of extra bookings only further established their advantage.
"It brought a lot of pain to Belgium people and fans". Jordan Pickford gathered a hopeful shot, almost, but he ended up spilling it into the path of Michy Batshuayi. And after a fumble by Pickford, Gary Cahill made a goal-line clearance. Calm down lads, you nearly scored there is what surely passed through Roberto Martinez's head.
'Tonight we've played OK.
Indeed, Martinez said before the match that Belgium's priority was not to win, suggesting he would choose a deliberately weaker starting line-up in the hope of missing out on the top of the pile. Belgium were winning - or losing, depending on what side of the fence you were sitting on.
Their final game presented the usual conundrum for teams already through with a game to spare: Do you try to keep the momentum going with your starters, or cycle in reserves to fight for a place and give the regulars a rest?
"We need to look at ourselves, we are a stronger group than we were before the game".
"Many debutants were desperate to be involved and that pleases me", he said. Or maybe it did. If they lose then this game will be viewed as the night when vital momentum was lost.
England manager Gareth Southgate believes it is foolish to plot a hypothetical route to the World Cup final with their poor record in knockout football over the past decade.
Rare that there is ever a moment to be so relaxed at a World Cup, but he has earned it. Southgate has been clear in his intention to let the players loose socially, to do their own thing, to treat them as responsible adults and let that permeate onto the pitch on match-days.