The Spanish fell behind to a Marcus Rashford goal early on, but Saul Niguez grabbed an equaliser fairly quickly and Rodrigo Moreno went on to hit the victor.
'When you think about the whole match, we deserved to win'.
"We aren't able to do that when teams press high against us yet".
"They pressed extremely well and it took us a while to work out where that press was coming from and find a solution to it".
"At the moment we have had initial discussions but that has been it".
"Now we have a choice".
"But there is a level for us to go to and that is a really good challenge for us over the next couple of years".
Against England, Spain had far less possession than they were used to under World Cup caretaker coach Fernando Hierro and predecessors Julen Lopetegui and Vicente del Bosque but played with more goal and were more direct than before. At the moment we have a different profile of player, we can't play the way that they want to play.
England were left to ponder their first competitive defeat at Wembley since they lost a Euro 2008 qualifier to Croatia in November 2007, a run stretching back 24 games - and also Southgate's first home defeat as manager. "I can't make decisions just to get a win", he said.
Rashford's opener, following an 11th-minute Luke Shaw cross, hinted at a performance and result that would extend the team's post-Russia honeymoon period.
Southgate also revealed he was contemplating switching back to a four-man defence in the coming months and, analysing the shortage of obvious replacements for Kane, appeared to end any hopes that Glenn Murray and Troy Deeney might have of a call-up. "I think he was a outcome of a unique talent". "I'm a fighter so I will be back soon!"
The game will be played at the King Power Stadium in Leicester, meaning Chilwell and Gray could be in line to make their senior worldwide debut at their club stadium.