Former All Black Aaron Cruden has been widely condemned for a "horrible" incident that saw him sent off in Japan after leaving Faf de Klerk sprawled on the turf.
Cruden inexplicably used his head and shoulder to clear out the South African scrum-half, connecting directly with his face during the Japan Rugby League One match between Tokyo Sungoliath and Canon Eagles.
The 17th minute clash makes for grim viewing and has sparked a strong reaction from fans.
Lobby group Progressive Rugby, who are campaigning for player safety and a clampdown on dangerous acts, said: "Almost impossible to understand what a hugely-experienced player with 50 caps for the All Blacks was thinking here. Horrible."
Former England World Cup winner Neil Back branded it as "a moment of madness" and viewers described it as "horrid", "nasty" and "thuggish".
Cruden, to his credit, made a point of apologising to his opponent before leaving the field after the TMO stepped in to review what happened.
De Klerk was also later yellow-carded in the match after taking out a kicker from an offside position.
Elsewhere in Japan, South African superstar Damian de Allende was sent off for Saitama Panasonic Wild Knights in their comprehensive 40-5 win over Mitsubishi Sagamihara Dynaboars for connecting with an opponent's neck in a another clearout.
The red cards come after Owen Farrell was lucky to escape a sending off in Friday night's Gloucester v Saracens game for a dangerous no-arms tackle. He is now expected to be cited and could potentially miss the start of the Six Nations.
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