Sterling went in late on Valencia with a reckless lunge down near his own corner flag, with the United man springing to his feet to grab his opponent around the neck.
|ECUADOR 2-2 ENGLAND
|MATCH REPORT: Rooney & Lambert strike but Three Lions falter in Miami|
Neither man will be suspended for any World Cup matches, but it will provide both managers with headaches with the tournament just over a week away.
Sterling, 19, had only been introduced as a 65th-minute substitute on the evening, but rather than impress boss Roy Hodgson he will have only prompted questions about his temperament.
Earlier on, Alex Oxlade-Chamberlain had been withdrawn with an injury following a challenge with Carlos Gruezo.
The Arsenal man missed much of the previous Premier League season through injury but was fit enough to walk from the pitch, albeit gingerly.
He had been in impressive form up until that point, providing several energetic runs to give England an outlet in the face of pacey Ecuadorian attacks.
England's Group D opponents Italy were also in action on Wednesday, but could only muster a 1-1 draw with Luxembourg.