Promotion candidate Union Berlin have signed defender Atsuto Uchida on a deal that runs through June 2018, the German second-tier side said Monday.

The 29-year-old Uchida, who spent seven years with Schalke in the Bundesliga, will reunite with his former Schalke manager Jens Keller as Union Berlin aim to return to the top flight after finishing fourth last season.

"I'm looking forward to finding out what awaits me," Uchida said on the club's official website.

"Of course I know Jens Keller well. I'm very happy that I'll be able to play soccer again."

Uchida joined Schalke in July 2010, after the World Cup in South Africa from the Kashima Antlers.