Is this the end for Kell Brook, or merely the beginning?

Saturday sees the return to action of British fighter Kell Brook after 18 months of very challenging events.

Brook was unbeaten in the summer of 2016 and one of the names mooted by many as a successor to the likes of Manny Pacquiao and Floyd Mayweather atop the welterweight ranks, with the two legends (at the time) retired from boxing.

He bravely decided to step in to fight middleweight Gennady Golovkin when Chris Eubank Jr had a sudden change of heart, but despite winning fans with his resilience and ability to land some telling shots, the gulf in natural size as well as class (Golovkin is perhaps the top fighter, pound-for-pound, today) swept away his ‘0’ and left him with a broken eye socket.

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His mouth-watering return to welter against fellow divisional star Errol Spence Jr started off as an exciting chance to get back to winning ways in some style. It finished, however, as a second straight defeat and a second straight eye socket injury.

Only now is ‘Special K’ ready to return to the ring, and he does so this weekend against Sergey Rabchenko in his debut at super-welter.

Those two defeats very nearly wiped out Brook’s career entirely, but now he sees the new division as a fresh start.

“I’ve got the butterflies and nerves just like it’s my first time getting in there,” said Brook.

“I think that I need to feel like that though, those nerves are going to make me sharper because I know that there’s a lot at stake on Saturday.

“I’m loving boxing again and things can change, and I still feel that I’ve got big fights left in me before I call it a day. I’d love to win a title at super-welterweight.”

On his opponent, Kell continued: “There was a list of fighters in front of us and Rabchenko stood out.

“He’s a very dangerous fighter and the fans might have let me off fighting someone lesser than him, but I wanted to fight him because I need to come back in a serious fight to stay switched on and not cut corners in the gym.

“You have to be professional. With a lesser opponent I might have enjoyed Christmas a bit more but not with Rabchenko, he’s a real threat.

“He’s boxed at a high level, been European champion, beaten my mate Ryan Rhodes – Ryan has boxed Canelo so to be stopped by Rabchenko it shows he is a good fighter and this is the right test for me in my first fight at 154lbs.

“Eddie named other fighters but I said no. I know that he’s a handful and he’s tough and clever. He’s calm and thoughtful in a fight, and I need a test like this. I can’t be half-hearted, I need to be fully committed and I will be for Rabchenko.”

For someone whose world championship status and unbeaten record two fights ago had him regarded as one of the best around, it’s absolutely vital Brook doesn’t lose a third straight contest. The concept of ‘three strikes’ may be a baseball thing, but it may as well apply to the boxing ring, as far as the Sheffield slugger is concerned.

That mentality was even apparent in some of Brook’s fight week words to the media, as he revealed that the Spence loss took away his passion for the sport, albeit temporarily.

“I’m not used to losing but I’ve had two in a row,” said Brook.

“The first one I jumped up to middleweight from welterweight against the most feared man in world boxing, so you can’t really take that as a loss, as it wasn’t my natural weight and it was a risk.

“Losing to Spence is a different kettle of fish as it was at welterweight, the other eye got smashed in and I lost my world title. That really hurt me badly, it took me a long time to get over that.

“I know that I’ve got a lot left in me, people are right to question what I’ve got left and how I am going to be after the injuries and the defeats, but I believe I am going to be the same fighter.

“I’ll be better with the bigger weight, which will bring the best out of me, but we can only see Rabchenko. I’m up for the challenge at the new weight, though.

“I do regret the Spence fight looking back. I was in Sheffield, we’d sold a load of tickets and we were in a football stadium – but going from middleweight down to welterweight was too much and it just drained me.

“But I was a proud champion and I never duck anyone. Errol is a class act and will dominate at 147lbs – hopefully I can get the rematch at super-welterweight.

“I’m loving boxing again and things can change, and I still feel that I’ve got big fights left in me before I call it a day.

“The eye has healed very well. It’s held up in sparring and I don’t think about the eye injuries at all. I wouldn’t be boxing if I wasn’t given the all clear by the doctors, I wouldn’t put my family or myself through that.”

It’s admirable that Brook genuinely feels ready to bounce back as if the Golovkin and Spence defeats didn’t happen. However, if Rabchenko is able to capitalise on the downswing and make it three on the bounce, it’s hard to envision the soul-searching having another happy ending.