Tim Tszyu could be in line for a world title fight after the WBO made the Australian the official mandatory for its super welterweight strap currently held by Brian Castano.
The WBO's ruling means Tszyu could fight Castano as soon as this year.
Castano is coming off a controversial split draw against WBC, WBA and IBF champion Jermell Charlo in July. Many observers had the Argentine winning the bout.
Tszyu is the number one contender with the WBO and IBO and is third with the WBC and IBF.
Last last year, Tszyu had been eyeing up a shot at the WBO title when Brazilian Patrick Teixeira held the belt.
Teixeira lost the belt to Castano in a one-sided unanimous decision in February before Castano's unification bout with Charlo.
A fight between Tszyu and Castano could be made for later this year unless Castano receives a exception to rematch Charlo.
Tszyu reacted to the WBO's news on social media on Saturday.
"You can run but now you can’t hide," he wrote.
"I’m Coming for ALL of it. #mandated."
Castano has previsouly said he isn't interested in a fight with Tszyu, telling The Daily Telegraph the Sydneysider needs more experience.
“Tim Tszyu is a good fighter, but I need a better fighter,” Castano said.
“I respect his career, but he needs more fights.
"He needs more experience and to fight other opponents."
There will also be significant negotiations around where the fight will be held.
“I need the fight here, not in Australia," Castano told the Daily Telegraph.
"Why he’s not coming here?
"I need the fight here, the people watch me, and they know me here in the USA. My work is here in the USA.”