"I am waiting for a text from my wife to say "get back home", he said.
"The more you watch a team, the more you start to see familiar patterns of play and how they build up".
"We'd been working for two or three years before that with the coaches in place at that time to try and make sure, through the pathway, that we got the right sort of experience in order to stand them in good stead".
The relatively low initial expectations and building enthusiasm around Southgate's youthful squad stands in stark contrast to the star names from earlier this century, who failed to match weighty demands from Three Lions supporters.
Southgate is credited with encouraging the warmer environment, far removed from the controlling regimes under Fabio Capello and Gary Neville, who was Roy Hodgson's assistant for the dismal 2014 World Cup and 2016 European Championship last-16 humbling to Iceland.
England's forward Harry Kane (L) and England's coach Gareth Southgate (R) give a press conference in Volgograd on June 17, 2018, on the eve of the Russian Federation 2018 World Cup Group G football match between Tunisia and England.
With the benefit of hindsight, perhaps that defeat will work out for the best for England team as it surely was the moment the country - and the media - realized the pressure heaped on the players was counter-productive.
Will you play a back three or a back four? Whatever Southgate decides, that trident will be primed to sow confusion among the Tunisian ranks.
"We grew up playing each other quite a lot and I was at Sheffield United with Kyle, he was a few years above me in the age groups".
The team, after all, blazed a trail in 1978 by becoming the first team from Africa to win a match at the World Cup.
Rooney had captained the team in a 2-0 Wembley win over Malta just three days earlier and expected to do so all the way through to this summer's tournament in Russian Federation. Under Nabil Maaloul, Tunisia is well-organized, particularly in defense.
England are looking to bounce back from unceremonious exits the past two tournaments.
The England midfielder said Emily Webb, England senior team operations coordinator and PA to Southgate, is ready to get him back as quickly as possible - and with the blessing of the England manager.