The heavyweights were in the United States to promote their June 1 world heavyweight championship fight, which has Joshua's four titles on the line.
But the face-off was over before it had even really begun because Miller put his hands on Joshua and pushed him so hard on the shoulders that the Londoner had to take a few steps back to regain his balance.
Watch the shove right here:
He also said he "respects war" and that he wants what Joshua has (presumably the heavyweight belts) and will therefore "take it."
After the shove, Joshua stepped to Miller but the two fighters were kept separate by event security.
Joshua will be able to get his hands on Miller for real on June 1 when they fight at Madison Square Garden in New York City, and the Brit perhaps rankled by that shove said he will "murder" Miller and knock him out by the fourth round.
The summer showdown will be Joshua's first bout in the U.S. as a professional.
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