Hanrahan had told the Sun that the England star "went berserk" after he made a joke about his £28 million transfer from Everton to Manchester United last summer. He said he walked past Rooney and said: "Once a blue always a blue, eh Wayne?"
Hanrahan, who is studying in Manchester, said: "He went absolutely crazy and swung his arms at me. He landed three punches - two on the top of my head and one on the right side of my forehead."
He claimed he also took two blows in the stomach from minders guarding Rooney and that England defender Rio Ferdinand stepped in to act as peacemaker.
The fracas erupted as Rooney drank with Ferdinand, defender Wes Brown and goalkeeper Roy Carroll at the club, near the hotel where England players were staying before the Northern Ireland game.
After going to the Sun, Hanrahan lodged an official complaint with police at the city's Bootle Street station.
Rooney always denied throwing any punches. The management of the nightclub have endorsed Rooney's suggestion that he was the innocent party and offered to provide United with witness statements and copies of CCTV footage.
A Greater Manchester Police spokesman said: "We were informed that the complainant did not want to pursue the allegation. We took a retraction statement from him and officers will not be pursuing the matter any further."
