Watson, 26, was arrested at 7:20 p.m. Saturday in Franklin. He is free on a $4,500 bond and is due in court June 28.
According to a Williamson County court affidavit obtained by The Associated Press, a Franklin police officer was flagged down by a witness to a possible domestic situation at a gas station. The officer noticed the passenger of a car "trying to back away from being shoved away." The report said the passenger said "stop" and was trying to cover her face.
Watson told police he and his girlfriend were having an argument and he admitted to pushing her. Officers said they found red marks on the woman's chest, and she said Watson had caused them.
According to The Associated Press, the affidavit says domestic assault is considered a Class A misdemeanor.
NHL deputy commissioner Bill Daly said in a statement that the league is aware of the situation and "it will be dealt with in due course and prior to next season."
Daly added "our focus currently is on the well-being and safety of Austin's girlfriend, their child and Austin himself. "
The team on Wednesday issued a statement saying it was aware of the incident.
"We are still gathering facts and it is not appropriate for us to comment further at this time, but this is a matter that we are taking very seriously and will cooperate fully with the investigation by law enforcement," the statement said. "The Nashville Predators have and will continue to stand side by side with AMEND in the fight to end violence against women."
The AMEND Together initiative (formerly called MEND) is a program of YWCA Nashville and Middle Tennessee, dedicated to ending violence against women through education. In 2017, Watson joined teammates Ryan Ellis, Mike Fisher and PK Subban as part of a public awareness campaign titled "Unsilence the Violence." In conjunction, the Nashville Predators Foundation pledged $500,000 to MEND.
Watson, selected by the Predators with the 18th overall pick in the 2010 draft, set a career-high in goals (14) and points (19) last season as Nashville won the Presidents' Trophy for the league's best record.
He scored eight points in 13 playoff games. Nashville was eliminated in the second round by the Winnipeg Jets.
Watson signed a three-year, $3.3 million contract last July. He has 23 goals and 24 assists in 216 career regular-season games, all with the Predators.
The Associated Press contributed to this report.