Some fans are not completely sold by the explanation as Garnacho also posted a cryptic image on his Instagram,.
One posted: "Alejandro Garnacho signalled he was changing his shirt before heading straight down the tunnel.".
NEW FOOTAGE has emerged to seemingly explain why Alejandro Garnacho marched down the tunnel after being subbed off.
Amorim opted to instantly replace Garnacho with Noussair Mazraoui to solidify the defensive side of the team.
Then, after United had recovered to lead 2-1, Dorgu saw a straight red card for a poor challenge on Omari Hutchinson.