Our head coach confirmed the corner routine was one from the training ground at Carrington, a plan hatched up by Jonny Evans and analyst Kaita Hasegawa.
The Reds capitalised after Cristian Romero's sending off when Kobbie Mainoo ran towards corner-taker Bruno Fernandes and laid the ball invitingly into the path of Bryan Mbeumo.
The Cameroon international kept his composure to roll a lovely finish beyond Guglielmo Vicario.
At half-time, Carrick told TNT Sports: "Yeah, it was Jonny, he has had his eye on set-plays, Jonny Evans, and Kaita, the analyst.
"So it's great when things come off.