Gareth Southgate accepted England made poor defensive mistakes in Tuesday's thrilling 5-3 defeat of Kosovo and demanded his side improve.
Raheem Sterling shone with a goal and three assists as England came from behind in an entertaining clash in Southampton.
Jadon Sancho struck his first international goals, with Harry Kane also on target, although the usually impeccable Three Lions captain failed to convert a second-half penalty.
Kosovo, though, forced regular mistakes from the Nations League semi-finalists, including in the first minute when a Michael Keane lapse led to Valon Berisha's opener.
Berisha would later profit again after Declan Rice gave the ball away too easily, while a Harry Maguire challenge resulted in Vedat Muriqi scoring a spot-kick.
England ultimately had too much firepower thanks to Sterling and Sancho but Southgate was under no illusions about the work to do in defence.
"It had its moments! A bizarre game really," Southgate told ITV after England extended their 100 per cent record in Group A.
"There were obvious poor errors for goals but I'm really pleased with the composure we showed.
"We had devastating attacking play throughout and we used the ball well.
"The mistakes were obvious, the errors, we have to be better. The players don't need me to tell them that.
"The outstanding parts of our play were obvious, the errors were obvious."
England return to action next month with away trips to the Czech Republic and Bulgaria.