How is this possible?

How can Mega Gnar push Master Yi out of his 'Q'? It just happened to me all game long. Master Yi "Q"clearly says Master Yi blinks to the target enemy and up to 3 consecutive nearest enemies, becoming untargetable in the process". I don't know if this is a bug but Mega Gnar ult should not be able to push Yi out of his "Q". If there is a reason on why this is possible I'd like to know because he would just keep cancelling my "Q" and it wouldn't do any damage.