Champion Kell Brook (36-1) first won the IBF World welterweight title in California against the heavily-favoured Shawn Porter and then went on to defend the honours successfully three times against Jo Jo Dan (34-2), Frankie Gavin (22-1) and Kevin Bizier (25-2).
He then dared to be great by stepping up to middleweight to face the fearsome Gennady Golovkin (35-0), resulting in his first and only career defeat.
Challenger Errol Spence Jr (21-0) is riding high after seeing off former European champion Leonard Bundu (33-1-2) and ex-World champion Chris Algieri (21-2) last year.
The American is undefeated in all bouts and the champion unbeaten at welterweight, which makes for a great fight and an extremely tough one to call so BBN asked their panel of experts what they think:
Bradley SaundersFormer Olympian and WBO Inter-Continental champion
“I’ve got to go with Kell because he’s a friend of mine but I definitely think he’s up against it.
Spence is no faker is he? He’s done jobs on Bundu and Algieri but if there’s anyone out there to beat him then it will be Kell Brook.
We’ve never seen Spence take one, he doesn’t get hit and he’s very clever. If Kell hits him then anything could happen and he’s very good with southpaws.”
Tommy LangfordBritish & Commonwealth middleweight champion
“My head says Spence but I really want Kell to win.
I can see a stoppage either way. Spence is very good boxer, the Golovkin punches that hit Kell were very hard but you can see them coming and brace for it, but with Spence you don’t see the punches coming as he makes you miss and makes you pay.
I know that Kell looks in great shape but if the weight has hurt him then we’ll see it in the ring. It could affect him, make him tire early.”
Darrel ChurchLight-heavyweight prospect
“I like Kell Brook and I think he’ll do it, I definitely think he can win on points. It’ll be a good fight.”
Paul HilzInternational Challenge Belt Champion
“I’ve always rated Brook but this Spence is a banger.
If Kell gets dragged into a fight then he might lose but if he boxes to the ability he can then he can beat the fella.
He boxed clever in the Porter fight so has got the ability to do that again if he doesn’t get caught up in a gun fight.”
Louis RobinsonDebutant
“I truly think Spence wins – he is very good.
Will Brook be drained and tire midway after dropping all that weight in just five weeks? We will see but I’m still going with a Spence victory here.”
Tim RicksonTR Sports Agency
“There’s question marks surrounding Kell’s weight but I think he’ll be ok. People are saying the weight will cause him to tire in the mid-rounds but I can’t see it myself.
Spence, I think, is the real deal, despite this being his first title fight. The way that he took out Bundu and Algieri showed his class and that he belongs at world level. How he gets on against a current world champion is uncertain still, we can only guess.
If Kell boxes like he did against Porter then he can edge a points win, however, I believe that he may engage Spence like he did against Golovkin and get stopped late on.
The fight with Golovkin proved his toughness and his heart but Spence’s shots will be different to GGG’s. His will undoubtedly be less powerful than the middleweight but they are unseen and sharp and stinging.
I think it’s a real pick ‘em fight but I’m edging towards Spence on skill and power.”
Ben DaySouthern Area champion
“I’ve been saying for years about Errol Spence, before anyone over here even knew about him – this kid is special and the future of boxing.”