By Edward Chaykovsky

A little more than ten years ago, former two division world champion Bernard Hopkins was the dominant fighter at 160-pounds. He became the first fighter to simultaneously hold the WBC/WBO/IBF/WBA world titles.

After suffering two decision losses to Jermain Taylor, Hopkins made a very unexpected decision to move up in weight - by two divisions - to face the top light heavyweight at that time, Antonio Tarver. 

Many felt Hopkins was making a big career mistake by jumping up by 15 pounds. He proved the critics wrong by dropping and easily dominated Tarver over twelve rounds to win a lopsided decision. At the time, Hopkins claimed the bout was the final fight of his pro career. He continued to fight until 2014 and has yet to officially retire.

Later tonight, another fighter will attempt to make a similar move - when IBF welterweight champion Kell Brook (36-0, 25KOs) will move up by two divisions and thirteen pounds, to challenge IBF/IBO/WBA/WBC middleweight champion Gennady 'GGG' Golovkin (35-0, 32KOs) at the full division limit of 160-pounds.

Golovkin will defend three of his four titles against Brook at the O2 Arena in London.

Hopkins believes an upset is always possible. He cautions that Golovkin is capable of hurting his opponent or getting a knockout victory at any point in the fight - so Brook will have to be careful at all moments.

"Going up two weight divisions, it's been done before - 10 years plus [back in time] by Bernard Hopkins. I went from 160 to 175 to fight Antonio Tarver, so anything is possible in boxing. This is a fight where both guys will really want to go out and set a tone early to prove that they are coming in to win. Triple G is dangerous any round, any second, any minute. Kell Brook will really, really have to be on his game," Hopkins said.