Couldn't understand this move at the time and understand it even less now. Zinchenko, Fernandinho and Ake were playing ok.Add to that Pep picking a side that have barely played together, then making a bizarre change when Ake went off, to make Fernandhino CB, and Zinchenko LB, to accomodate Gundogan as some sort of hybrid DM/AM (no I've no idea where he was meant to be playing), and playing Mendy's useless twin at LM, and it's quite frankly no surprise we lost
If he wanted to bring in Gundogan then take off a straight replacement or move Zinchenko back in place of Mendy.
If his purpose was to replace Ake, then put on Garcia.