Ospreys and Wales Sevens player Ben Cambriani, 20, from Mumbles, Swansea, attacked Oliver Clare in the city’s Fiction nightclub on 31 January 2019.
Judge Niclas Parry told Swansea Crown Court Cambriani “couldn’t hold his drink”.
Cambriani pleaded guilty to assault occasioning actual bodily harm and was given a suspended four-month sentence.
The jail term was suspended for a year. He was also ordered to carry out 100 hours of unpaid work and pay £1,000 to the victim for his dental work.
Prosecuting barrister Sophie Hill said the defendant was “shouting” at the complainant, before striking him with “a clenched fist to his nose and mouth”.
The victim suffered a bleeding nose and a chipped front tooth in the attack and required a filling and smoothing of his tooth, “as well as two crowns and further treatment which is not available on the NHS”, she told the court.
The court heard after the attack Cambriani was escorted by bouncers to a room in the nightclub where he offered to pay them money to let him go, which was refused.
Cambriani’s barrister John Hipkin QC said: “I am instructed formally to apologise to Mr Clare for what he did to him that night.
“The defendant is 20 years of age… and he has a promising sporting career which this has substantially dented.”
Sentencing Cambriani, the judge said: “[You] acted like a yob not an athlete… You let yourself down, and all of those who’ve supported you in reaching your goals.
“You did that because you couldn’t hold your drink and you punched a complete stranger to the face….
“Go back to being the achieving young man that you are, put this behind you, and make sure that you comply with the order.”