The English Football Association (FA) have formally requested to increase the sanction for Millwall goalkeeper Liam Roberts following his sixth-minute sending off against Crystal Palace in the FA Cup on Saturday.
Roberts was dismissed following a VAR check for serious foul play after charging out at Palace attacker Jean-Philippe Mateta and kicking him in the head.
In a statement, the FA wrote that the usual punishment for serious foul play was "clearly insufficient" in this case. The standard ban for a straight red card for serious foul play is three matches.
Millwall acknowledged the FA's position in a statement of their own and said they would fight against any extension of the punishment.
"Millwall Football Club acknowledges the FA's statement and will continue to support Liam who has been subjected to horrendous online abuse since Saturday's collision," the statement said.
Mateta was treated on the pitch for several minutes after the challenge before being immediately taken to hospital from Selhurst Park and given 25 stitches for a "severe laceration" to his left ear. He was discharged later that evening.
Palace's chairman Steve Parish described the incident as "the most reckless challenge" he'd ever seen.
Millwall posted a statement criticising media coverage of the incident after the game, saying the reaction amounted to "character assassination" of Roberts.
"The club are disgusted by abuse directed towards goalkeeper Liam Roberts following Saturday's unfortunate collision with Jean-Philippe Mateta," it read.
"The reporting on the matter, as well as disgraceful suggestions made by certain news organisations and high-profile figures within the sport that Liam intended to harm Jean-Philippe, has contributed to the unwarranted character assassination of Liam and fuelled abhorrent online abuse towards him.
"No player at Millwall Football Club steps on to the pitch with the intent to harm another, and the club will continue to support Liam, who reached out to Jean-Philippe personally on Saturday evening with an apology which was accepted immediately."
Millwall fans held a minute's applause for Roberts in their Championship match against Bristol City on Tuesday.