One Sidharth Mahajan had accompanied a guest, Sukhvinder, to the party at Yuvraj's house in DLF Phase I and allegedly started misbehaving after having drinks.
According to Yuvraj's mother Shabnam, the police were called and Mahajan was told to leave.
However, Mahajan's mother Neelam claimed it was her son who was beaten up by the cricketer before being thrown out of the party.
Both the dashing cricketer and his 'unruly' guest have lodged complaints with the police, who were investigating the matter but yet to register an FIR.
Mahajan had named Yuvraj Singh, his mother and his friend and actress Kim Sharma, as persons responsible for manhandling him.
Yuvraj, who missed Team India's South Africa tour with a troubled knee, reportedly sustained some injuries in the incident.