IT’S win or bust for Nathan Cleverly in the gambling hotbed of Las Vegas this Saturday as he puts his WBA world light-heavyweight crown on the line against Badou Jack.

The 30-year-old Welshman and poker fan is going “all-in” to win the fight and break into the “elite hierarchy” of boxing.

Cleverly eased to a points victory over Antonio Baker on his Vegas debut in April 2008 – there is considerably more up for grabs in the prize pot this time around.

The victor will likely be handed a showdown with WBA ‘super’ champion Andre Ward, and Cefn Fforest’s finest doesn’t want to miss out on the chance of a seat at the sport’s top table.

“We are at the stage of my career that any defeat could be the end,” he said.

“I’m at the highest level and I’m here to stay.

“Defeat is not an option. I’m all-in with this fight because if you win you’re in the big time.

“There are a lot of world champions in boxing but to break through that elite hierarchy, which is what the top fighters love, then I have to win this fight.

“I probably won’t reach this level again if I lose. It’s now or never for me.

“I’m two-time world champion but before I get out of boxing I want to reach that elite level.”

He added: “Andre Ward is the elite fighter in the division – one of the best around.

“He is a special fighter and that type of fighter only comes around once every generation.

“I think Ward is a smart, smart guy, in and out of the ring, and he knows his weight division is light-heavy.

“I think he will sit patiently and consider all options, specifically take a closer note of this fight because ultimately the winner is mandatory for Ward’s ‘super’ title.”

Cleverly hit the casino tables to celebrate that defeat of Baker almost a decade ago – that bout took place on the undercard of Joe Calzaghe’s epic win against Bernard Hopkins.

Nine years after his Vegas bow, Cleverly is again taking his place on a show which features a headline act – Floyd Mayweather versus Conor McGregor – that has got fans talking.

Speaking before he headed out to Nevada, the former British, Commonwealth and European champion described that much-hyped contest as a “freak event”.

It isn’t one that is going to distract Cleverly from his preparations, and neither are the slot machines and poker tables.

“If you want to be big in boxing you come to Vegas,” he said.

“This is my seventh time. I came out just before Christmas after my world title win (against Juergen Braehmer last October).

“But this time we are here strictly on business, this is not about Las Vegas leisure side, it’s all business.

“We have done our work back home and we are maintaining that.

"I can’t be distracted now. We are all-in until the fight now.”

Meanwhile, former WBC world super-middleweight champion Jack, 33, has vowed to knockout his rival.

He said: "I can’t wait to put on a show on Saturday night. I’m going to knock Nathan Cleverly out.

"This is the best camp I’ve had of my career. I have an amazing team and we’ve worked well together.

"I’m ready to get in the ring.

"This is the biggest stage you can be on."