Undefeated junior middleweight contender Tim Tszyu was ringside on Saturday night at the Dignity Health Sports Park in Carson, California - and watched Jermell Charlo set the record straight by knocking out Brian Castano in the tenth round of their rematch to become the undisputed champion at 154-pounds.

In a very competitive fight, Charlo scored two knockdowns in the tenth to stop Castano and unify the WBO, WBA, WBC, IBF world titles.

Tszyu is the mandatory challenger to the WBO belt.

The popular Australian star has made it clear that he wants the fight with Charlo to take place in the United States.

“If the boys try to convince me to fight [in Australia], I’m going to tell them that I want to go there [to the United States],” Tszyu told The Sun-Herald.

“America is so big, the land of opportunities and dreams is endless. One-hundred thousand pay-per-view buys here in Australia is massive, a massive fight. One-hundred thousand in America is dog shit. So you can’t even compare.

“If you become a pay-per-view star in America, you’ve made it worldwide. The money, the status, everything triples. I’m in this game for a little bit, so I have to make the most of every opportunity. I’ve got to fight in places where I can only dream about. One day I will retire and will be living here in Sydney, kicking back. I’ll be able to talk about the things I did in my life.”

Tszyu, son of Hall of Fame fighter Kostya Tszyu, made his American debut a few weeks ago in Minneapolis with a solid decision win over Terrell Gausha.

He hopes to secure the fight with Charlo before the year is over, but the undisputed champion will have several mandatory obligations to deal with.

“I want a mega-fight, I want Charlo,” Tszyu said. “That’s my cup of tea.”