Joe Sharratt, 18, previously played for Chorley Panthers and also represents Lancashire and England at Schoolboy level.
The teenager, who has recently signed with the St Helens Academy, was injured in the early hours of Sunday outside Factory nightclub in Manchester.
An investigation has been launched and police are appealing for anyone in the area at the time to get in touch.
Chief Inspector Cherie Buttle of Greater Manchester Police said: “We’re aware that there are a number of videos circulating on social media and I cannot stress how important it is that those with footage make contact with us.”
“He represented Lancashire Schoolboys against Australian Schoolboys with distinction on Saturday and was hoping to represent England next weekend.”