The Under-19s, coached by Nicky Butt, face Real Sociedad at the AJ Bell Stadium at 14:00 BST on Wednesday, a few hours before the senior sides play in the Champions League at Old Trafford.
The UEFA Youth League, in its inaugural year, mirrors the main competition at this stage and Sociedad are on top of United's group after winning both of their opening fixtures.
With the competition designed to give young players a taste of what to expect from the tests that lie ahead in senior football, Welbeck hopes that there will be a good show of support for Butt's side on Wednesday afternoon.
"They had a good crowd out in Donetsk so it would be good if we could get some fans to the game before ours," he told MUTV. "You get to see the future of Manchester United, and future talents from all around the world. I'm sure it will be a great game of football.
"It's invaluable to the younger players. They travelled with us to Ukraine, stayed in the same hotel, played before us, then got to watch the actual first team game. It's a great experience to get into that mode early doors. You have to get accustomed to playing against different teams and different styles, and the earlier you get used to that, the better it will be in the future so it's very beneficial for them."
Watch the Under-19s in action
Executive Club members, Season Ticket holders and Official Members can gain free entry by texting UNDER19 + your membership number to 60777. Production of membership card is required at the gate. Entry is free for Under-16s, all other supporters can purchase a ticket for £3 from the AJ Bell Stadium ticket office. MUDSA members can purchase tickets by calling 0161 868 8009.