By Edward Chaykovsky

Martin Murray would love to back his countryman Kell Brook in next Saturday's fight, but he fears the IBF welterweight champion will be overpowered and chopped down to size within six rounds by IBO, WBC, WBA and IBF world middleweight champion Gennady Golovkin.

Golovkin (35-0, 32 KOs), who stopped his last 22 opponents, will defend the titles against Brook (36-0, 25KOs) at the O2 Arena in London.

Murray (33-4-1, 16 KOs) is the only fighter to last eleven rounds with Golovkin. He was battered and stopped last February by the middleweight king. It remains the only stoppage loss of Murray's career.

Murray believes the size difference will be too much for Brook to deal with. Brook is heading up by thirteen pounds to meet Golovkin at the middleweight limit of 160-pounds.

He says Brook won't be strong enough or big enough to do what is necessary to beat Golovkin. In fact, Murray says nobody at the middleweight level has the proper tools to unseat GGG from the 160 throne.

"It's a step too far for Kell," Muray told Nick Parkinson. "Golovkin is another level and he's in deep, deep water and I don't think he's going to be able to swim.

"I don't think Kell can go as long as I did with him. I think it goes five rounds, six maximum, and I know what it is like in there with him. It could go early. I've gone the longest with Golovkin and to beat him you have to move well, which Kell does, and you have to push him back. That's how you beat him but I don't think anyone is strong enough at middleweight to do that.

"Kell has got great range, distance and timing so Golovkin is going to be in with something different himself. But Golovkin's distance and timing are something else. He's in a different league to anything I've fought and Canelo [Saul Alvarez] won't touch him.

"Golovkin really hurt me with the body shots he took me down with. I gritted my teeth and got back up but when those body shots hit you, you don't recover. It was the same with [fellow Briton] Matt Macklin [who Golovkin knocked out in three rounds in 2013]. It was the little shots he hit me with as well, the range finding shots, and he's just on a different level.

"Kell has been in some hard fights like when he fought Carson Jones and he's improved since then. He showed grit to win that fight against Jones because at one point it didn't look like he would. But Golovkin has not once looked like he would get beat. Fair play to Kell for taking it because this is not his natural weight. He's obviously getting well paid for it and he gets to keep his welterweight title and he was struggling to get the fights he wanted at welterweight."