One world champion. One devastating punch. One definitive answer.

What more is there to add? Plenty actually, and you can read all of it on the BBC Sport website. We'll have a fight report, quotes from both camps and look out for a blog from our man at ringside, Ben Dirs, tomorrow morning.

Thanks for your company tonight. Until next time...

John Mulgrew:, external That's a punch that would knock anybody into next Wednesday!

Dan: Post fight comments from Froch and Groves are a credit to boxing. Excellent. Good stuff gentlemen.

Rids: The apprentice got too cocky for the sorcerer last time and just got given a lesson in manners.

Craig: Boxing is an art. I've more respect and more impressed with George and Paddy's skills than a one-punch wonder. Pundits are annoying. Giving it all after the event know it all, predicted it all.

BBC Radio 5 live

George Groves's former trainer Adam Booth, speaking to BBC Radio 5 live: "George opened his arm out for the left hook. It is something we talked about from day one but if you make a mistake like that then you will lose. I could see from the first round that Carl was sweeping that left hook across. He was doing that to keep George occupied. George looked a little heavy on his legs at times and when Carl senses the time was right that is when he made his move. It was sad to see.

"You cannot be naive against a guy like Carl Froch. Underestimate at your peril because he is a tough old man that is a lot smarter than his style and age shows.

"He has to go back and lick his wounds for a while and look at what he did wrong. He has to rebuild but he is young enough and wise enough."

BBC Radio 5 live

More from Eddie Hearn on the future for Carl Froch: "This is the pinnacle for him but he is still fresh at 36. James DeGale is the mandatory, there are a host of others and I can deliver those for Carl. I don't think the decision will be made by Carl, it will be Rob McCracken, when he decides, but tonight is not the night.

"Domestic fights sell. DeGale is the mandatory but Carl has got fights he wants. It is my job as promoter to push that fight for DeGale but Froch has so many things to do with his career still and we will find a way to appease everybody."

James DeGale, who is now the mandatory challenger for Carl Froch's world title belts, speaking to Sky Sports Box Office: "I thought it was a good fight, but cagey for the first six rounds and a wicked finish from Carl Froch. He's always had the power and Groves's chin has always been the problem. That punch would have stopped anybody, but you have to think how he got hit with it - it came from a long way out. That would not happen to me. Styles make fights and I've always said I'm Carl Froch's worst nightmare. I've done my part of the deal tonight and now Eddie Hearn has to deliver [on the world title shot with Froch]."

BBC Radio 5 live

More from Rob McCracken: "I am being totally honest. I want him to have a break, we will have a chat and see what he wants to do. He lives like a monk, he is thoroughly dedicated to the sport. He will want to do a big one, he will want to do one in Vegas but we will have a chat.

"He will have a month off from listening to me. He loves the sport, he is a gladiator."

BBC Radio 5 live

Carl Froch's trainer Rob McCracken, speaking to BBC Radio 5 live: "He boxed to the plan. We felt if he controlled the centre and pushed Groves back, eventually the right hand would pay off.

"It was a huge fight for him, being in Britain. His legacy is hugely important to him. He can solve puzzles in the ring, he can deal with extreme speed and deal with power too. He is tremendous.

"It was a tremendous right hander he threw. In fairness to Groves it was very tricky to pin him down. He is very quick and I am sure he will have a tremendous future but Carl is a power puncher and when he connects you are going to go."

Image source, Getty Images

Kalle Sauerland, the promoter of George Groves, tells Sky Sports Box Office: "Carl Froch's chin - what Mikkel Kessler and George Groves have detonated on it - it's amazing, what a fighter he is. For George, he put in a performance that I can go out and sell. I am 150,000% certain he will become a world champion one day."

BBC Radio 5 live

Promoter Eddie Hearn, speaking to BBC Radio 5 live: "Carl is very clever. He is under-rated as a fighter. His style is not orthodox but he is very smart and clever. George has the attributes to beat Froch, he is faster, he moves well but Froch knows what he has to do to win.

"It is one of those where you score what you like. Froch was forcing the fight, forcing the pressure, we knew Groves was going to try and out-box Froch.

"George is such a good kid, he was gone but still tried to get up. He is a great fighter, but Froch deserves so much respect. Look at his record, look at where he has been. He deserves it. Yes he earned a lot of money tonight but he could not give a monkeys. He never thought about the money, he is a fighting man and he loves to fight. George will come back again but Froch, at 36, it is fantastic."

Carl Froch heads back into the changing rooms - it's time for some behind-the-scenes selfies with his coaching and management team.

BBC Radio 5 live

Carl Froch, speaking to BBC Radio 5 live: "That was a great right-hander. I timed it perfectly. I was trying to close down George, at times the crowd were getting a bit bored but I was not going to force it. I was biding my time and I knew as soon as I landed it correctly, on the chin, on the jaw section of cranium it would be all over and it was. It must be the best punch I have ever thrown and landed in my life. It is not going to get any better than this. It was absolutely fantastic.

"George is very quick, he buzzed me a bit with a shot, so I had to take my time. I have 12 rounds in me, I executed my gameplan perfectly and there you have it, he has his leg wrapped around him and it was sorry sight for him in the end. He came in very confident, probably over-confident. I think it was a little bit deer in the headlights, but he brought it on himself."

"I would like to fight again. I think the way I took him out there, I was not in a war there. I would love to fight in Las Vegas."

Andy McNamara:, external You get the feeling that a big punch like that will attract a big money match in Vegas. They like 'big' in Vegas.

Incapable Hulk:, external It seemed like Groves got too wrapped in the media side of things, whilst Froch looked more focused on preparation.

Ian Bennett:, external What a punch, what a fighter. Carl Froch must surely now be regarded as one of Britain's best boxers.

Promoter Eddie Hearn: "Everything was on the line for Carl tonight, there was so much pressure on him but what a champion he is. It is not time to talk about who he will fight again, it is time to celebrate tonight. Time and again, Carl has done it, years and years, and all over the world. He deserves the respect. He was always going to be judged on tonight and he delivered with massive pressure on his shoulders."

More from Carl Froch: "I showed tonight why I am a four-time champion of the world. Why I have defended it 13 times consecutively. The ending showed what makes someone elite for many years.

"The next opponent? Who knows, I will listen to my trainer Rob McCracken."

Listen to fight reaction on BBC Radio 5 live by clicking the 'Live Coverage' tab on listen on the radio.

Image source, PA

Following the fight, Froch got down on one knee in front of his long-time girlfriend, Rachael Cordingley. The champ explains: "I told her how much I love her. I didn't officially propose - I couldn't sort the ring out. But I will be marrying her. Tonight will be remembered for defending my titles but I did ask Rachael a sneaky question. It's not official. She said yes."

A special night indeed.

Carl Froch: "I'd love to box in Las Vegas, it ticks a really special box for me. It's the fight capital of the world. I will never top boxing in the national stadium in front of 80,000 people. To put boxing on this platform is special - I'm very proud. My children will look back and say: 'That was my daddy in there.'"

George Groves on the bad blood between the two boxers: "It is boxing, the fights are hyped. I don't like or dislike any of my opponents. I'd love to come again. I was ahead on the scorecards until that point and I'll be pushing hard to get my world title shot and if Carl is still boxing maybe that will be against him.

"Yes (it's a learning experience). I'm young enough. I will learn and improve. I made a silly mistake. I left my chin open. All the imperfections need to be corrected. We'll come back stronger. It's back to the drawing board. We've got no excuses. Tonight is all about Carl, it's his night now."

A defeated George Groves tells Sky Box Office: "I am fine. It is boxing. Fair play to Carl, he caught me. I thought I was doing very well in the fight but it is boxing. I have to hold my hands up and I'll come back bigger and better and stronger.

"I feel like I let myself down but congrats to Carl, fair play. He got the punch and I congratulate him."

A victorious Carl Froch tells Sky Box Office: "I'm feeling unbelievably elated. This is the best moment in my boxing career. I've been involved in some magnificent fights with top, top world champions. This is by far the biggest and best crowd I've boxed in front of. I'm proud. George Groves should be proud. It was neck and neck in there. There was nothing in it. Sometimes in boxing it only takes one punch and unfortunately for George he was on the end of a very heavy right hand."