The 28-year-old former World No. 1 also pulled out of Cincinnati citing a "family matter."
Victoria Azarenka could be forced to miss the U.S. Open due to a custody battle with her child's father, according to a TMZ Sports report.
According to the report, Azarenka and Billy McKeague split up in July, after Wimbledon, and McKeague has filed for custody for their eight-month old son in California. TMZ is reporting that a judge told Azarenka that the child cannot leave the state until the dispute is settled, and Azarenka is unwilling to leave the child with McKeague because she does not think he is capable of caring for him. Azarenka reportedly has a valid custody order from Belarus, but the judge won't defer to the Belarus court.
The dispute is reportedly not going to end before October at the earliest. The U.S. Open kicks off on Aug. 28.
Azarenka, 28, pulled out of the Cincinnati Open on Friday, citing a "family matter." When contacted by SI, a rep for Azarenka declined to comment on the situation.
Azarenka has won two Australian Open titles and became World No. 1 in 2012. She is currently ranked No. 203, though she only returned to tennis in June after taking extensive time off to give birth to her son.