Cahill had tangled with the forward throughout the game in Yokohama - settled by Paolo Guerrero in the 69th minute - but their tussle came to a head moments before the final whistle.
The centre-half was shown a straight red card for kicking out at his opponent but was adamant he had been provoked.
"He lashed out with his arm and hit me in the face," Cahill said.
"Someone's smashed me in the face but I didn't roll around on the floor for five minutes holding my head.
"I got up, reacted and tapped him in the shin. He felt the need to go down, roll around on the floor for about five times holding his face.
"It probably is a red card but the reaction of the guy is totally out of order for what I did if you see the impact.
"It wouldn't have been enough to knock over my one-year-old daughter."
FIFA have confirmed Cahill will serve a one-match ban, missing Wednesday's Capital One Cup quarter-final at Leeds, though a disciplinary panel will review the punishment as a matter of course this week.
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