Young was scoring for the first time in over 19 months when he rocketed in from 20 yards.
But just as importantly, he seems to have heeded David Moyes' demand to cut out the diving.
"I have spoken to Ashley and I have said, make sure you do everything right. And he did," said the Scot.
"He got kicked a few times and he went down, but he got back up and got on with it.
"He has shown he can come in and make an impact. That is what I need.
"We have got a lot of competition in wide areas at Manchester United, and a lot of players we can select from.
"If you want to get regular outings you need to score and you need to play well."
Young provided the opportunity for Patrice Evra to curl home a rare right-footed effort and leave United well placed to reach a first final since Moyes replaced Sir Alex Ferguson, and the mouthwatering prospect of a Wembley showdown with Manchester City.
Moyes is looking that far ahead, though.
"Sunderland have just had a really good result against Chelsea and we are going to have play well over the two legs to get to the final," said Moyes.
"When the draw was made it looked like Chelsea, Tottenham, maybe us, and (Manchester) City.
"But you never know in the cup competitions. We certainly won't be taking anyone lightly in the semi-final."
There was some good news on the injury front too for United, with Moyes confirming Wayne Rooney could be fit to face West Ham on Saturday after missing the Stoke trip with a groin injury.