The 42-year-old watched his side take the lead against the Liga champions and then miss several opportunities to extend their advantage before two goals from Lionel Messi inspired Barca to a victory that returned them to the top of the table.
Emery's men have now failed to win in their last five matches, but the former Valencia boss remains positive that his young squad will learn from their latest loss.
"It was a good match but we lost out in decisive areas," he said.
"It should be said that for many of our lads, this is their first experience at this level.
"They need to play more of these games to come out and play with confidence - so this game will help them in the long-run."
Defeat on Sunday left Sevilla seventh in the table, six points behind Real Sociedad, who occupy the final UEFA Europa League qualification place.
Manchester United eyeing surprise move for AC Milan star for whom tension in Italy is growing: report
‘Even though Kevin Keegan was my boyhood hero, we never really saw eye-to-eye. That was an underwhelming time for me – I felt on the outside’: Newcastle cult hero reveals disappointment over how things went under King Kev
