United suffered a convincing 3-0 defeat at the Nou Camp on Tuesday night, adding to the 1-0 loss at Old Trafford last week to send Ole Gunnar Solskjaer’s side crashing out of the quarter-finals.
In the wake of the defeat, racially abusive messages were posted on social media site Twitter from a series of anonymous accounts about England international Young, labelling him a “f****** n*****” and an “ape c***”.
United have said that they “will take the strongest possible action” that is available to them and that it “utterly condemns” the “racist social media comments”.
Furthermore, the club are “working to identify individuals involved”.
Anti-racism group Kick It Out issued a statement to highlight the abuse to Twitter, and called on the social media giants to “take serious action to tackle the rampant discrimination” across the social media network.
“Yet another black player, this time Ashley Young, targeted with racist abuse on social media after tonight’s Champions League game,” the Kick It Out Twitter account posted on Tuesday night.
“Again, we’re left asking @TwitterUK the same question - when will you take serious action to tackle the rampant discrimination on your platform?”
But a Twitter spokesman refused to comment on the specific abuse posted about Young. "We do not comment on individual cases for privacy reasons," a Twitter spokesperson said.
"Our abusive behaviour policy prohibits behaviour which attempts to harass, intimidate or silence another person's voice and we take strong enforcement action if violations are found.
"Progress in this space is tough, but we are deeply committed to improving the health of the conversation on the platform.
"To this end, we are now suspending three times more abusive accounts within 24 hours after receiving a report than this time last year. We'll continue building on this work to prioritise the safety of our users."
Young started the second leg in Barcelona at left-back in the absence of the suspended Luke Shaw and found himself targeted by Lionel Messi, who prospered from United’s defensive troubles by scoring twice in the first half.
But the match has been overshadowed by this latest incident of abuse, which follows a series of issues across England as well as racist chanting aimed as England internationals including Danny Rose and Raheem Sterling during the Euro 2020 qualifier victory over Montenegro last March.