By Edward Chaykovsky

The boxing world was once again stunned on Friday, when Matchroom Boxing and K2 Promotions announced that a deal was finalized for Gennady Golovkin to defend his IBF, WBA, WBC and IBO Middleweight World titles against IBF Welterweight champion Kell Brook at The O2 in London on September 10, live on Sky Sports Box Office and HBO World Championship Boxing.

Golovkin (35-0, 32KOs) was in deep negotiations to fight Chris Eubank Jr. but there were issues with Eubank dragging his feet to sign the contract. There were ongoing talks for a unification between Brook (36-0, 25KOs) and WBO world champion Jessie Vargas, but that fight was having issues with finalizing the money for Brook - because Vargas wanted a high seven figure sum to travel over to Sheffield.

Two fighters apparently fell out and were morphed into one.

Brook follows the lead of his domestic rival Amir Khan, who in May moved up by eight pounds to face Saul 'Caenlo' Alvarez for the WBC middleweight title. Khan started off well but got knocked out, in brutal fashion, in the sixth round.

Brook - who has an undefeated record and regarded as one of the top welterweights in the world - is taking an even bigger risk. Brook is heading up by thirteen pounds

The Sheffield fighter is not worried about the weight and believes he will shock the world.

“This is the fight and the moment I have been waiting for for some time,” said Brook. “We've tried and tried to lure the best to come and fight me and now we've got the best of the best – the number one pound for pound fighter in the world is coming to the UK.

“When this fight got offered to me I accepted within minutes and I can't wait. Everyone knows I'm a huge welterweight and I know I will carry my speed and accuracy and even more power through the weights. This is the ultimate fight, one of the biggest international fights the country has seen in many years - you have seen some huge names run from GGG but I'm running to him. I'm a Special fighter and I will show the world on September 10.”