Southgate added that he does not like "codes of conducts" and questioned why this issue had come about on the eve of the World Cup, but he believes Sterling is capable of moving on swiftly.
After Saturday's tune-up encounter against the Three Lions at Wembley, the three-time African champions wrap up preparations for the Mundial with a friendly against Czech Republic on June 6.
Overall the match was a real positive for England, but the second-half display shows Southgate still has work to do if his team are to make an impact in Russian Federation.
"The game will be a hard one because they parade some of the best legs in the English Premier League, but we also have guys who have played there and are still playing there, so we will put up a good fight and come out with a victory", Simy concluded.
"I talk to all of the players at length because I think it's important, as a coach, to get to know them and what makes them tick and what they're about as much as possible", he said.
" "Les aides sociales, des " trappes à inactivité " selon Gérald Darmanin
Et d'expliquer à propos de la prime d'activité , destinée à encourager les chômeurs français à retrouver un travail: "En 2016 quand la prime d'activité a été créée, c'était 4 milliards d'euros ".
It's hard to read too much into worldwide friendlies, but Gareth Southgate's side looked like World Cup contenders in the first half.
There are so many of them, the usual scenario you experience when some coaches will say they don't have a team, some will say they are lacking in one department or another, are they native doctors?
"The first half we felt comfortable, moved the ball quickly and dominated but a lack of concentration early in the second half let us down".
Alli is widely recognised as one of the finest talents in Gareth Southgate's squad but his place in the starting XI is in doubt following, by his standards, a less convincing season with Tottenham.
Captain Harry Kane doubled England's lead as he picked up a loose ball and leashed it past Nigeria goalkeeper Uzoho. We don't want to see that happen again.
England were impressive with their movements in the last third and took a deserved 2-0 lead into the break while the Super Eagles were disjointed and looking nervous. With those two setting the tone, the rest of the England side followed suit and the Three Lions were able to largely nullify Nigeria.
Iwobi's goal summoned more confidence in the Nigerian players and they had chances to equalise.