Steve Borthwick labelled England's 30-21 Six Nations Round 3 defeat to Scotland "a painful lesson", bemoaning errors that allowed the hosts "easy scores".
A sublime hat-trick from Duhan van der Merwe helped Scotland to a 30-21 victory over England as they kept their Six Nations hopes alive.
Scotland claimed the Calcutta Cup for a fourth year in a row and returned to winning ways after a controversial loss to France in Round 2.
England took an early lead in an untidy first half through a converted George Furbank try and George Ford penalty to lead 10-0, but they would not lead again as a host of handling errors saw Scotland into a comfortable lead and, ultimately, victory.
"Today has been a big learning experience and a real painful lesson," Borthwick told media afterwards.
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"They were very clinical. A huge lesson for our team as we develop is the number of turnovers, it makes it very difficult to win.
"It is very difficult to win, especially against a team of Scotland's quality.
"I think we can respect what a good team Scotland are and the chances they took but ultimately we made it too easy for them to score.
"We all love progression to be a nice linear path but ultimately it is not, especially at this level.
"This is a team that is trying to develop, trying to add layers to the game and made errors today and got punished for them.
"Sometimes you get away with them. Sometimes you don't. Against a team like Scotland, you don't.
"As you look at it, against a Scotland team that has been together a long time. Their 10, 12, 13 have played together over a dozen Tests and I think that is the first time our 10, 12, 13 have played together and it showed.
"It looked like a lack of cohesion and too many fundamental errors."
England next host Six Nations leaders Ireland at Twickenham in Round 4 on Saturday, March 9 (4.45pm kick-off), while Scotland travel to play Italy earlier on the same day (2.15pm kick-off).
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