Ultimate Fighting Championship shocked the Mixed Martial Arts-loving world this week, as they traded away top Flyweight fighter Demetrious Johnson.

In the first deal of its kind in the company, Johnson has signed for Singapore-based promotion ONE Championship, and in-turn, UFC have been given top Welterweight Ben Askren, who is unbeaten in 18 contests.

In letting Johnson leave, the UFC have let go of the man who dominated the Flyweight division for six years, defeating every challenger that entered his sights.

Ian McCall, John Dodson, Joseph Benavidez, Henry Cejudo - they all fell at the feet of 'Mighty Mouse'.

His undefeated streak that stretched back to October 2011 was ended though in August at UFC 227, where Cejudo avenged his 2016 loss with a Split Decision victory to capture the Flyweight belt.

Many expected a rematch to take place, but murmurs of a historic deal between UFC and ONE started to occur, and yesterday saw official confirmation of Johnson's departure, and Askren's arrival.

Askren has called out every big-name fighter under the sun in the last week or so, and is really making waves on social media, getting a response off Darren Till in the process.

A former UFC Champion who wanted to get his opinion across on the whole deal is former Middleweight king Michael Bisping, who thinks the Flyweight division is in serious danger.

“Sad to see [Demetrious Johnson leave] from a personal perspective but does this mean the end of the flyweight division?” Bisping asked on UFC Tonight, per MMA Mania.

“I mean if the UFC are willing to let Demetrious Johnson go - as I say the face of that division - does that mean they’re going to cancel the 125 division?

“Force them to go fight at 135 or force them to go fight for ONE FC out in Asia. Who knows? A lot of questions.”

It seems really unlikely that the company would just discard a whole weight class, but whilst Johnson was dominating the division, he wasn't exactly a pay-per-view draw at the same time.

Despite everything, Bisping has paid tribute to Johnson, who will surely go in the Hall of Fame sooner rather than later.

"It's sad to see Demetrious Johnson go,” said Bisping.

“This guy trailblazed the flyweight division. He was the guy. He was the face of it.

“Of course, he lost to Henry Cejudo recently but I still believe he’s one of, if not the best pound-for-pound fighter in the world. So it’s sad to see him go.”