Kell Brook plots Errol Spence shock as George Groves looks to end world title wait

Listen to BBC Radio 5 live commentary of Brook v Spence & Groves v Chudinov from 21:30 BST on Saturday

IBF world welterweight champion Kell Brook will "relish" being a bookmakers' underdog against an opponent he believes will provide "many problems" on Saturday.

Brook, 31, defends his title against American Errol Spence Jr at Bramall Lane, home of the club he supports, Sheffield United.

He meets the unbeaten and much-hyped 27-year-old at 147lbs, having fought two divisions higher when he suffered a broken eye socket in defeat by Gennady Golovkin last time out.

"I think there will be a lot of drama," said Brook. "We could both maybe hit the canvas."

There will be enhanced security at a stadium which has not hosted boxing since 1984, when about 3,000 fans attended.

Up to 27,000 will be present for a night which features two world title contests as co-main events - George Groves also faces Russian Fedor Chudinov for the vacant WBA world super-middleweight strap.

Promoter Eddie Hearn said it is "important for the whole country that major events go ahead without disruption" in the wake of Monday's attacks in Manchester.

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'I will not let luck play a part'

Groves believes this is his "best opportunity" to land a world title at the fourth attempt after a tumultuous three years, losing twice to Carl Froch - once at a packed-out Wembley Stadium - before being narrowly out-pointed by Badou Jack in Las Vegas.

That 2015 defeat by Floyd Mayweather's fighter prompted 'Saint George' to join trainer Shane McGuigan and four wins have followed.

"Yes I've lost three title shots but I don't feel beat up, I don't feel exposed," said Groves, 29. "This time I am not going to allow it to be close. Everything is in my favour and we are in a good place to go and win."

Groves is expected to win and is hopeful Chudinov's recent inactive spell of just one fight in 20 months will prove key. But Chudinov, 29, has lost just once in 15 fights as a professional - losing the WBA title to Felix Sturm, who later vacated the belt and tested positive for steroids.

It will likely be a career-defining night for Groves whatever the outcome. But while he admits to feeling "pressure" as favourite, he has been quick to call on boxing to show solidarity following Monday's Manchester attacks.

"You're hoping there's a British sprit of 'we are not going to let these people beat us'," he told BBC Sport. "It gives events like Saturday more purpose. A terrible thing happened but in the same week we are going to show strength."

'I want it with all my heart'

Brook-Spence Jr will be televised in the US, with Stephen Espinoza of the Showtime network stating the bout has received "tremendous attention" across the Atlantic.

Spence, who competed at London 2012, has been dubbed "the real deal" by former five-weight world champion Sugar Ray Leonard and insists he will make it 22 wins from 22 fights to take the title.

"It's going to be another man down," said Spence. "I'm looking to come forward, I won't be taking a backward step."

Brook was encouraged to move up a weight division after the defeat by Golovkin, which resulted in him having titanium placed into his eye socket.

But he defied advice and stayed in the division to make his fourth - and undoubtedly toughest - defence of the title at a venue which he first visited as a fan aged seven.

"You'll have to rip this belt off me," said Brook. "There are question marks over Spence, he has never been in with anyone like me or even close to me.

"He will give me many problems. An ex-Olympian, a very good fighter, he has knocked over whoever he has come up against. But I want it with all my heart."

Calorie deficits - the Brook slim down

Trainer Dominic Ingle possibly saved Brook's career in throwing in the towel against Golovkin. He has since set about rehabilitating the Sheffield fighter, after a first loss in 37 career fights, at his training base in Fuerteventura.

Brook weighed about 12st at middleweight on fight night against Golovkin and has since therefore lost over a stone and a half to make welterweight, a challenge given he has always been seen to be physically big in the division.

"Train dirty...eat clean" is Brook's mantra for staying in fighting condition

"Kell burns around 2,500-3,000 calories a day," Ingle told BBC Sport. "He operates on a calorie deficit so he will take on 500-1,000 less than what he burns. That works out at about 2lbs a week in fat loss."

Brook trims the timber with three runs a week, where focus is on speed and power through treadmill sprints rather than long endurance-based runs. On run days he will also do pad work in the afternoon.

On two other weekdays he conducts a sparring session in the morning and weights after lunch, while a Saturday can often throw up a 30-mile bike ride to shed more weight.

Analysis - Two factors in Brook test

BBC Sport boxing correspondent Mike Costello:

There are two key factors in this fight. One is the talent of Errol Spence Jr. We've seen from the opposition he has faced so far that he is pretty special but he's never been hit as hard as he is going to be hit on Saturday, how he reacts to that will be key.

The other factor is how Brook has lost his weight. He has never been comfortable at this weight and we have seen boxers in the past struggle to come down when they have put weight on, especially if it is muscle. How he reacts to boiling down will be key.

I do have a feeling this will be really special. Brook has the experience, Spence has the talent. This is Brook's toughest ever challenge at welterweight.

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