Death threats made against Wigan rugby league player Ben Flower, who punched an opponent as he lay on the ground, are being investigated by police.
A series of abusive Twitter remarks have been posted on an account, directed to Flower, who was sent off in Saturday's Super League Grand Final.
Flower received a six-month ban for hitting St Helens former-Kiwi stand-off Lance Hohaia.
One comment on the single account said Flower's "last days are approaching".
Other Twitter messages said that Flower "deserves to be shot", adding that he is a "dead man".
Greater Manchester Police (GMP) tweeted: "We've been made aware of abusive social media activity about the Rugby League Grand Final. Please be reassured that we are looking into this."
More than 70,000 fans at Old Trafford and millions of television viewers saw the player hit Hohaia, who lay motionless on the ground just two minutes into the match.
St Helens chairman Eamonn McManus said after the ban: "We must assist [Flower] in any way that we can and accept him back into the sport. There is a person behind the player, and I am reliably informed by all that it is a good one."
Mr McManus also said of the punching incident: "These matters have to be dealt with by the appropriate body within the game and it has so been."
A GMP spokesman said any decision to take action against Flower would depend on conversations it had with St Helens.
The Wigan prop Ben Flower has been handed a six-month ban for the punches on New Zealand playmaker Lance Hohaia that marred the Super League grand final at the weekend.
The Rugby Football League's disciplinary tribunal took just half an hour to come up with the punishment after Flower admitted the grade 'F' offence.
The RFL announced the verdict via Twitter.
Flower's punishment amounts to a 13-game ban, comprising two pre-season trials, Wigan's World Club Challenge meeting with Brisbane Broncos on February 21st and the first 10 games of the 2015 Super League season.
It is the second heaviest ban of the Super League era.
Terry Newton, the late former Great Britain hooker, was suspended for 10 matches for knocking out Lee Gilmour and breaking the cheekbone of Sean Long while playing for Wigan against St Helens in 2005 but the ban was extended to seven months when his appeal was rejected.
Wigan rugby general manager Kris Radlinski, who accompanied Flower to the hearing at the RFL's headquarters in Leeds, said there would be no appeal.
Hohaia also accepted a one-match ban for a grade 'B' striking charge just before the incident occurred.
St Helens beat 12-man Wigan 14-6 in the final at Old Trafford.
Greater Manchester police are liaising with the game's authorities, St Helens and the Crown Prosecution Service over what course of action should be taken, though the New Zealander says he doesn't hold any grudges against Flower, and people do some things they regret in the heat of the moment.
Hohaia says he's done some silly things on the field himself, and he's probably more disappointed in himself for not being able to play a part in the game as well.
In a statement on Wigan's website, Flower said he's "devastated" by what he had done.
"I firstly offer my apologies to Lance. I have full respect for him, and have never gone onto a rugby field to injure a fellow player.
"I'd also like to say sorry to my team-mates, our fans and the Wigan Club. I know I've let them down like never before and accept I'll have to live with this for the rest of my career.
"Finally, I'm sorry to the sport of Rugby League. It was a big night and I know I've taken the attention away from what was a special event."
Hohaia was unable to return to the field because of concussion and will have scans this week before hopefully being cleared to fly out with his family for a holiday.