The Bayern Munich striker starred in their 1-0 Champions League win on Tuesday night against United, who finished bottom of Group A and thus have no European football left this season.
Kane provided an excellent assist for Kingsley Coman for the winner, a deft touch with his right foot into the path of the Frenchman.
Bayern’s star man had a quiet night overall until then, but there was an incident in the first half that saw his tempers flare.
Garnacho and Coman fought for the ball towards the byline at the Stretford End, with the latter crashing into the advertising boards.
Fan footage from right next to the incident shows Kane cutting bitterly unimpressed figure with the United youngster.
He ran up to Garnacho and exchanged furious words with him, with United captain Bruno Fernandes having to somewhat restrain him.
It did little to deter Kane though as he continued to express his frustrations, this time with referee Espen Eskas.
Once again, United players intervened as Raphael Varane held him back and Harry Maguire had a little word in his ear.
England captain Kane is normally not one to confront players on the pitch. However, with the 30-year-old still yet to win a major trophy, he may be beginning to show more grit as he sets his sights on silverware.
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