Manchester United delivered a 7-0 mauling of Barnsley in midweek, with 20-year-old Alejandro Garnacho pulling the strings. If there was one thing missing from an all-round complete performance, it was the restrained approach Erik ten Hag took with the academy players. Toby Collyer did start as a fill-in left-back, his first start for the club, yet this was also determined as a snub for Harry Amass, who starred in his natural position in pre-season. Ethan Wheatley did make the bench, having made his debut last season. Yet with United 5-0 up, Erik ten Hag decided to send on Joshua Zirkzee instea…