It was at the end of a long question-and-answer session in the early-afternoon sunshine of Croissy-sur-Seine, the affluent town west of Paris where England are preparing for their final assignment of the season, that someone asked Gareth Southgate if he was ever tempted to find easier opposition.

On Tuesday night it is the Stade de France to meet the finalists of Euro 2016. England’s last foreign excursion was to play in Germany and they will meet the world champions again at Wembley in November. Southgate’s team have already taken on Spain and, continuing the theme, there is the possibility of a game against Holland in Amsterdam next March. England, Southgate freely admitted, are deliberately making life hard for themselves.

The reason says a lot about their manager when, barring a win in France, England will go into the summer break after only three wins from eight matches since the Football Association promoted him from his role with the Under-21s. Those victories have come in World Cup qualifiers against, in order, Malta, Scotland and Lithuania – the teams 182nd, 61st and 104th in Fifa’s world rankings – and Southgate acknowledged it was inevitable his win ratio would “probably get spouted out at some point” if the Football Association continued choosing elite opposition.

At the same time he also made a credible case why it was the logical decision when England’s opponents have been so moderate during their long unbeaten run, stretching 35 matches to October 2009, since they were beaten in any qualifying fixture. “It would have been easy for me to ask for easier teams to try to manipulate our ranking and think about my own win percentage, but what’s the point?” Southgate said. “We have to test ourselves against the best. It’s the best way to learn and improve. It’s about the evolution of the team and how we get better. We have to challenge the lads, with or without the ball, to perform at the highest level.

“Tactical details, things we need to improve upon. If we are playing teams who play with a low defensive block all the time, that’s one problem we have to resolve. But we also have to play teams who come at us. Can we play out? Can we break down really high-quality defenders? We need these different type of challenges.”

That process will continue here with a new goalkeeper taking over from Joe Hart. Two, in fact, bearing in mind Southgate will start with Tom Heaton – “statistically, the highest-performing English goalkeeper in the league” – and then replace him at half-time with the fit-again Jack Butland. Hart, Southgate insisted, was still the established No1 but the manager has had time now to analyse the two free-kicks from Leigh Griffiths at Hampden on Saturday and, for all his diplomacy, it was noticeable he could not excuse England’s goalkeeper of any blame.

Likewise Southgate was unwilling to say Hart, with his club career in limbo, would return to the starting lineup when England resume their World Cup qualifying programme against Malta and Slovakia in early September. “Joe has been excellent for us. The two goals at the weekend were the first he has conceded in this qualifying campaign and we owe him for the point in Slovenia [the 0-0 draw last October] after one of the best saves I’ve ever seen. His contribution has been excellent since I’ve been manager. That said, I don’t want anyone to feel completely comfortable in their position because I’m not sure that’s healthy.”

The loser here is actually Fraser Forster, a regular of England’s squads but now the odd man out at a time when Southgate has taken the unusual decision to include four goalkeepers and is also keeping in mind Karl Darlow from Newcastle United and Brighton’s David Stockdale.

“I’ve spoken to him [Forster] and, of course, he’s disappointed,” Southgate said. “He’s travelled quite a bit with England and not had the number of matches he would have liked. I’m conscious that’s very difficult because I was close to Nigel Martyn when he was doing the same. We’ve got the four guys who are with us, we’ve got Jordan Pickford who will come into the equation and a couple of others with the teams that have been promoted. It’s hard to keep all those guys happy. But I wanted Fraser to be part of this squad because he is close. I’ve had to make a decision about this game and I can’t make him feel any better other than to communicate with him and show him that respect.”

Harry Kane will continue in his new role as captain, a trial that is expected to be made into a full-time position in the autumn, but Southgate is intending to field an experimental side otherwise and has moved John Stones into a defensive midfield position in at least two training sessions over the past week.

Stones was left out of the Scotland game and there is a passage in Tony Adams’s new book when the former England captain, a man who knows a thing or two about the art of defence, describes Manchester City’s £47.5m signing as “average” and claims the most expensive English defender in history reminded him of Tony Gale – reasonable on the ball but not good enough, defensively, to win international honours.

Southgate, however, offered a more positive appraisal and will bring Stones back into the team for his 18th cap. “John has huge potential. Defending is a skill you learn and he’ll learn a lot with a coach [Pep Guardiola] asking a lot of him with the ball. Next season, at club level, he’ll be much stronger for what he’s been through: the move, being at a club where so much is expected of him, the transfer fee and everything surrounding it. He’s become a father. There’s a lot going on in his life and he will be a much better player for those experiences.”