Nathan Cleary urged people to stop sending Phoenix Crossland abuse and threats, calling the hip-drop tackle an accident and saying he had "nothing but respect for him."
Newcastle forward Crossland was given a four-match suspension on Tuesday for the tackle that broke Cleary's leg during Sunday's preliminary final.
The ban rules Crossland out of this Sunday's grand final against the Sydney Roosters and all three of New Zealand's Rugby League World Cup pool matches.
He could play again if New Zealand reaches the semi-finals.
Crossland pleaded guilty and apologised to Cleary, his father Ivan, the Panthers and the wider game during an 85-minute judiciary hearing.
"It's been the worst couple of days of my life," Crossland told the panel, adding that Cleary was "my favourite player by a mile".
Cleary underwent emergency surgery at Sydney's Royal North Shore Hospital on Sunday night.
Knights counsel James McLeod argued for a ban of no more than three games, while NRL counsel Patrick Knowles SC said four was appropriate.
Judiciary chair Geoffrey Bellew said missing a grand final was irrelevant under the code.
Cleary also asked online users: "Spread love, not hate."