Nagazaki confirmed the deal on Tuesday morning having completed the formalities, as reported by FourFourTwo on Friday. 

"I'm very glad to join V-Varen Nagasaki and I am deeply grateful for the warm welcome of the club officials," he told the club website. 

"There are style and cultural differences in Japan, but I will give my best for V-Varen Nagazaki."

The 25-year-old midfielder had only managed 10 appearances for Heidenheim during the 2017-18 season and needs game-time to boost his chances of selection at the 2018 World Cup.

Halloran played all three matches at the 2014 World Cup but in the past three years fell out of the national team frame under Ange Postecoglou, who resigned as Socceroos coach in November.

The speedy Australian has six Socceroos caps, the last being in September 2014.

Nagazaki earned promotion from the J2.League for the first time in 2017, finishing as runners-up.