By Edward Chaykovsky

WBA welterweight champion Keith Thurman (27-0, 22 KOs) is still shaking his head at Kell Brook's decision to jump up by two weight divisions to challenge IBO/WBA/WBC/WBO middleweight champion Gennady 'GGG' Golovkin last month.

Brook had his moment in the fight, but the size and power of Golovkin was evident as the fight played out. Brook's right orbital bone was fractured in the second. Once his vision began to fail him and he started taking punishment in the fifth, his corner threw in the towel.

Thurman views Brook (36-1, 25KOs) as one of the best fighters in the weight class, but he's not confident that Special K will fully recover from that contest.

Brook recently underwent surgery due to the injury and won't again until next year at the earliest.

Thurman told Premier Boxing Champions - "Brook is one of the best athletes in his weight class, but he’d never moved around with 15 extra pounds for 12 rounds. I wanted to get in his head like, 'Why are you doing this? You haven’t faced a 147-pounder like myself yet, and you haven’t even faced a 154-pounder like Canelo [Alvarez], and you’re going to go in there with Triple G?'"

"I hope that he received the best paycheck of his career and invests in the best doctors and physical therapy, [because] it could play out as a very horrible business and career decision. I would love to see him return to [147 pounds], where they can market him as an undefeated welterweight. I hope he’s not vulnerable to easy injury or to other left hooks from power punchers."

Brook is not sure if he'll return to the welterweight division. If he does, then he owes a mandatory obligation to unbeaten Errol Spence. The IBF will order both sides to begin negotiations on October 26th. Many believe Brook will return as a junior middleweight.

No matter what happens, Thurman expects Spence to capture the IBF belt.

"One way or another, Errol Spence is getting that title. Kell Brook can vacate if he wants no part [of Spence], and Errol could get it by fighting a non-champion. But I’ve always loved the idea of an Errol Spence-Kell Brook fight or Thurman-Kell Brook," Thurman said.