Leeds Rhinos reported full-back Zak Hardaker to the police after identifying a photo of him that was released following an assault.
Hardaker, 23, and academy player Elliot Minchella, 19, both paid £200 in compensation and wrote a letter of apology after admitting assaulting a student.
Rhinos coach Brian McDermott told BBC Radio Leeds: "We were the ones who rang the police. We alerted Zak and Elliot that they needed to go to the police.
"This is a blip and hopefully in our internal investigation we can find some positives in this and turn it around and some people can learn valuable lessons."
Hardaker started at full-back for the Rhinos in their 26-14 victory over Wigan Warriors on Friday night.
