Chatri Sityodtong, CEO and chairman of One, told a conference call last week former UFC lightweight champion Eddie Alvarez was “the first of many signings of global superstars” for his organisation.

“We’re upgrading our roster everywhere,” Sityodtong said. “We’ll make some major announcements. You guys will be surprised.

“Every free agent should think about One if they want to fight on the biggest stage and get paid like a world champion should get paid. That’s our proposition.”

“Mighty Mouse” Johnson would certainly fit the bill, having gone 13 fights undefeated with 11 title defences before his majority decision loss to Henry Cejudo in August.

The 32-year-old is still number two in UFC’s pound-for-pound rankings despite his legendary reign being snapped, and reportedly has multiple fights left on his contract.

However, Johnson’s head coach at the AMC Pankration gym, Matt Hume, also serves as One’s vice-president of operations.

Former Bellator welterweight champion Askren, 34, is undefeated in 18 fights with one no contest, and announced his retirement after a first-round victory in just 57 seconds against Japan’s Shinya Aoki last November.

But Askren tweeted on Monday there was a “98 per cent” chance of him joining UFC. He had also mentioned after the Aoki fight he was interested in returning to face UFC welterweight legend Georges St-Pierre or current lightweight champion Khabib Nurmagomedov.

“Now you’re all in big trouble,” Askren wrote in another tweet after the news of the potential trade broke.

A former Olympic wrestler for the US, Askren competed at the 2008 Beijing Games. He made his professional MMA debut in 2009 and joined Bellator in 2010.

The American signed a two-year, six-fight contract with One in December 2013, and is considered one of the best fighters never to have competed in the UFC.