The exact viral incident described by the original title could not be verified confidently, so specific actions should not be invented.
Large male kangaroos can stand close to human height and may use upright postures, forelimb grappling and powerful kicks during fights. Human encounters become especially risky when an animal feels cornered or has become accustomed to people.
Large Males Look Intimidating

Adult male kangaroos can become tall, muscular animals with powerful shoulders, forearms and hind legs. Standing upright allows a male to assess an opponent and prepare for the wrestling and kicking behavior used during competition with other males.
Boxing Starts With Grappling

Kangaroo fighting is often described as boxing, but the animals do more than strike with their forepaws. Males grab and push one another while balancing on their large feet and tail, creating opportunities to position the opponent for a much stronger hind-leg attack.
The Tail Becomes a Support

During fighting, a kangaroo can lean backward and use its thick tail as additional support. This frees both hind legs to kick forward together. Long claws on the feet make that movement capable of causing serious cuts and other injuries.
A Human Can Look Like a Rival

Habituated male kangaroos may approach people more closely than normal. If a person faces the animal, raises their arms, blocks its path or moves toward it, the kangaroo may respond defensively or interpret the posture as a challenge.
Feeding Increases Risk

Wildlife authorities discourage feeding kangaroos because animals that associate people with food may lose their natural caution. A large male that confidently approaches humans can become difficult to manage, particularly if it expects food and does not receive it.
Do Not Square Up

People should not imitate kangaroo fighting postures, attempt to punch the animal or approach for a close photograph. The aim should be to reduce confrontation by moving away calmly, keeping obstacles between yourself and the kangaroo and leaving it a clear route to escape.
Dogs Can Trigger Conflict

Kangaroos may perceive dogs as predators. A kangaroo pursued by a dog can turn and defend itself, creating danger for both the pet and an owner attempting a rescue. Dogs should be restrained around wild kangaroos and kept away from resting animals.
Distance Prevents the Fight

A six-foot kangaroo standing upright makes dramatic footage, but a close encounter should not become entertainment. The safest outcome is one where the animal never feels forced to grapple, kick or defend itself against a person.
Featured Image: Photo by Taylor Johnson on Unsplash