By Edward Chaykovsky

Middleweight contender Matthew Macklin knows a thing or two about IBO/IBF/WBA/WBC middleweight champion Gennady 'GGG' Golovkin.

Macklin faced him in June of 2013 and was knocked out in the third round with a huge hook to the body. Macklin went down for the count when the punch connected.

On September 10th at the O2 Arena in London, Macklin's good friend - IBF welterweight champion Kell Brook, will challenge Golovkin for his middleweight titles. Brook is moving up by thirteen pounds for the contest.

According to Sky Sports, Macklin visited Brook in training camp and gave him some advice and pointers to use against the dangerous puncher.  

Macklin told Brook: "You cannot allow him to read you. He is a very intelligent fighter; he is not just a puncher. He never really caught me with a big shot to the head. Your jab is a ramrod but so is his so I'm curious to see how that goes when the battle of the jabs occurs in the fight.

"What I found with him is his punches were quite unorthodox and his balance was exceptional. That was the thing that stood out to me along with how quickly he was able to cut the ring off so it is important that your movement is very good in this fight."