Gennady Golovkin will defend his IBF, WBA, WBC and IBO Middleweight World titles in Britain this year – but NOT against Chris Eubank Junior.

Brighton's Eubank Jr, 26, had been expected to sign a deal this week to face the middleweight king but Eddie Hearn's Matchroom Boxing have announced IBF Welterweight champion Kell Brook will meet the US-based Kazakh at The O2 in London on September 10.

It is a stunning twist which has taken the boxing world by surprise.  

But Brook said: "You get fighters saying they want to fight the best but they don't step up to the plate.

"Eddie (Hearn) put this to me 24 hours ago and I said yes straight away. Everybody is running away from Triple G but I am running towards him. I want these big fights."

The two unbeaten stars collide in London with Golovkin, 34, stepping into the ring as a defending champion for the 16th time in his first fight in the UK.

Eubank Jr has swapped messages with Golovkin on social media with the Kazakh claiming the deal was done as far as his team were concerned and just needed the Brighton fighter to sign.

Brook will move up two weight divisions for the fight.

Eubank Jr responded on social media to the announcement by tweeting: "I haven't been shown one contract since my fight with GGG was announced. I'm still ready & waiting to sign. Fighting Brook is a joke #2Small"