The MMA community was shook up Wednesday afternoon when ESPN's Ariel Helwani reported that the UFC and ONE Championship were close to finalizing a deal to essentially swap Demetrious Johnson for Ben Askren. No "trade" like this has ever taken place in the sport, and now it is happening with one of the pound-for-pound best ever and an undefeated welterweight who was champion in two promotions.

Let's break down the most crucial questions raised by this unprecedented move.

Is the trade done?

No, but it is close to being completed. Both sides, according to Helwani, are ironing out the final agreements.

Is this an actual 'trade'?

No, not per se. Because it involves two organizations and fighters under contract, the athletes cannot simply be swapped. Johnson will be released from his UFC contract, freed to sign with ONE. Askren will be released from his ONE contract, freed to sign with the UFC. Both sides have agreed that these eventual signings will occur.

Who is involved?

Demetrious Johnson was the UFC's first flyweight champion. He defended his belt 11 consecutive times to break Anderson Silva's UFC record. That streak ended in his most recent fight in August, when Henry Cejudo won a close split decision. Before that, Johnson was ranked as ESPN's top pound-for-pound fighter.

Ben Askren was a four-time All-American wrestler at Missouri, claiming two national titles. He competed in the 2008 Olympics. After college, he began training in MMA and eventually signed with Bellator. He became the promotion's welterweight champion in 2010 and defended the title four times before leaving to sign with ONE. He won that promotion's belt in 2014. After his last defense, in November, he announced he was retiring. He remains undefeated.

What is ONE Championship?

Of course you know the UFC. ONE Championship? Some may have scratched their heads wondering why the UFC's longtime flyweight champion would want to leave for a smaller organization. ONE, however, isn't as small as you may think. The Singapore-based company is one of the largest global sports media properties in Asia. The promotion's Kingdom of Heroes card earlier this month had 25 million viewers across all platforms, according to Nielsen. ONE, founded in 2011, signed former UFC and Bellator lightweight champion Eddie Alvarez last week to a deal he says is worth "eight figures."

Demetrious Johnson is set to join ONE Championship, where his coach, Matt Hume, left, is vice president of operations. Todd Lussier/Zuffa LLC/Getty Images

Why did the trade happen?

Askren, 34, decided to retire as ONE's welterweight champion after four years of dominating competition in the organization. He felt he had achieved what he needed to. That said, when he made the choice to step away, he acknowledged that he would return for the right bout. It could come sooner than later with his entry into the UFC. There's no shortage of potential opponents who would be of interest, including longtime UFC welterweight champion Georges St-Pierre.

Johnson's aim to leave the UFC is a bit more complicated. He has had problems with the promotion over the years based on financial incentives and PPV points. Despite his supremacy in the division, he believes the UFC did not market him enough to make him the superstar he saw himself becoming. The flyweight division, the lightest fighters on the roster, have typically drawn lower viewership numbers compared to other weight classes.

Another factor for Johnson's interest in this move could be his strong relationship with Matt Hume, his head coach at AMC Pankration in Kirkland, Washington. Johnson, 32, will know exactly what to expect from his new home, as Hume is also vice president of operations for ONE Championship.

Is the UFC's flyweight division in jeopardy?

This remains to be seen, though the UFC has not drawn strong viewership numbers for fights in this division. Now, with flyweight's biggest star gone and with current champion Cejudo expressing interest in challenging bantamweight champ TJ Dillashaw, questions remain about the long-term viability of the weight class.

Whom could each fighter face in his new organization?

The obvious first opponent for Askren is St-Pierre. The longtime welterweight champion recently told ESPN he would come back only for fights that would greatly impact his legacy. This could be that fight, as GSP would be facing an undefeated, two-promotion champion.

Johnson should step in and fight for ONE's flyweight belt immediately. That means facing Geje Eustaquio, a Filipino fighter who claimed the title earlier this year. He's 11-6 in his professional career.