The Reds were beaten 8-7 on penalties in a marathon shoot-out after the 90 minutes ended with Jose Mourinho and Frank Lampard’s sides locked at 2-2.
After Juan Mata's third-minute opener was cancelled out by two second-half Derby goals, United had goalkeeper Sergio Romero sent off but Marouane Fellaini scored an injury-time equaliser in a breathtaking finale.
However, the Rams won the penalty-kick climax in front of the Stretford End, and the Reds' captain for the night, Young, felt his team should have matched Derby’s intensity in normal time.
“I am not sure we have done enough in the 90 minutes to manage to win the game,“ said the skipper.