WHEN Anthony Joshua challenges IBF world heavyweight champion Charles Martin on Saturday night, the eyes of the British boxing world will be on the O2 Arena. However deep on the undercard, Matthew Macklin and Brian Rose will put friendship aside to fight for the sake of their careers.

Their paths have run curiously parallel to one another over the past few years but on Saturday night, they converge in a fascinating middleweight clash.

In 2013, Macklin’s world title hopes seemed crushed for good when middleweight kingpin Gennady Golovkin savaged him in three rounds. A year later, Rose was outclassed by super-welterweight standout Demetrius Andrade, who stopped him in seven.

They were both underdogs, and there was no real shame in falling short at the elite level. However after some minor rebuilding, they both suffered much more worrying reverses. Jorge Heiland knocked Macklin out in 10 rounds while Carson Jones stunned Rose in the opening stanza of their meeting.

The regrouping process was harder this time around, but they both managed it in their own ways. Macklin picked up a couple of wins before struggling past the limited Jason Welborn in October. It was a wake up call for the 33-year-old.

“The last fight, Jason Welborn, I sparred Peter McDonagh and a kid from Glasgow who was 2-0 at the time called Marc Kerr,” he told Boxing News.

“They’re not on the level I should be sparring at, you’re not sharp, you don’t move your head and you drop to that level. And I think you take that with you into the ring on the night.

“As much as you never want to disrespect a fighter, and you do respect every one you face, some fights you can get up for and some you can’t. For the life of me I could never envisage Jason Welborn giving me that sort of fight.

“The fact I managed to navigate my way through the 10 rounds and dig in despite not being up for it shows a bit of toughness. It also gave me a bit of a kick up the arse.”

Rose faced Jones in an immediate rematch and handily outpointed the rugged American, which is perhaps why he is the slight favourite ahead of Saturday night.

“It was more getting rid of my demons,” he said.

“I couldn’t sleep after the first fight, and I blame myself for that loss. The rematch helped me mentally more than anything. I always knew I was a better fighter than him, I just needed to win that rematch and move on so I could sleep at night again.”

Macklin insists he has ‘fallen back in love’ with boxing during his camp for this fight, which has seen him spend time in the States to spar with Jason Quigley.

After seeking advice from Bernard Hopkins, Macklin claims he has listened to his body more for this fight and has eased off his preparations when needed.

“It was what I needed, I got away, focused on the boxing and fell in love with it again really,” he said.

“I did a lot of work with Jason Quigley, great lad, really talented fighter. He’s at that stage of his career where he’s super enthusiastic, super excited about everything and after 15 years in the sport it’s hard to get that enthusiasm back up.

“So it was good to be around that and feed off it and just fall in love with boxing again. 15 years is a long time, it’s a love/hate relationship.

“I’ve trained hard, trained well, taken days off when I’ve needed to, puked up several times as well. I’ve given it everything, but I haven’t overdone it either. I think I’ve found the right mix, which is hard to find.

“Sparring Quigley, he’s a really sharp kid and he was at the end of his camp so he was razor, and I was only just starting mine so I hard to sharpen up. I had to sharpen up just to stay in there! I need those butterflies, I always have. That’s why I’m an on-the-night fighter. I need the nerves.”

For Rose, the change in this camp has been preparing for his first fight at middleweight. Having fought at super-welter – where he won the British title – his whole career, Rose is enjoying the freedom of not having to worry about boiling down to 154lbs.

“I feel great in training, I can only go off my training. I’m not thinking about my weight now, I’m just thinking about getting fit and the tactics,” he said.

“It’s been hard in the past, people don’t know but I’ve really struggled making light-middleweight. Since moving up I feel strong in the gym, I think later in the rounds I’ll have a second and third gear and I think I proved that against Carson Jones the second time.”

Much has been made about how badly a loss would affect either man, particularly on such a big stage (the fight will be shown on Sky Sports Box Office in the UK). However, to the victor, the spoils. With the spurious IBF Inter-Continental title on the line, a ranking with that organisation is assured.

If the fight lives up to the hype it has received from those ‘in the know’ so far, whomever prevails will enjoy a further enhanced reputation. Both are fully aware of that.

“A win puts you back on the world scene,” Rose said.

“The IBF Inter-Continental belt is on the line so it’s the easy IBF route to Golovkin [laughs].

“I just want to fight for a world title again and perform at the highest level, whether I win or not, I just don’t want any more regrets when I retire.

“My one regret is when I fought Demetrius Andrade, I froze on the night, froze on the big stage. He’s a better fighter than me, I hold my hands up but I just feel against the right world champion, I can do it.”

Macklin also has ambitions to get back on to the world stage.

“The win for me, if I perform the way I should it’ll be a good performance and I’ll dominate,” he said.

“I don’t want to disrespect him and say I’ll knock him out in a round or six because he might show balls he’s not shown before and stay in there.

“I haven’t really called anyone out because I probably wouldn’t be ready for them. If I perform well and I feel good, and once I’m confident it’s still there I will be calling out the likes of [WBA ‘regular’ champion] Danny Jacobs.

Of course, both are aware of what’s at stake. Macklin in particular feels his will be fighting for his career on Saturday night. Indeed, it’s hard to envisage either man coming back to a notable level should they lose.

“If I lost I would retire, 100%,” Macklin said.

“If I can’t beat Brian Rose, I wouldn’t have the audacity to call out Danny Jacobs. And that’s no disrespect to Brian Rose, I think he’s a good fighter, that’s why I’m taking this fight. He’s probably a European level fighter, he’s not world class though. I think I’m a better fighter and I’ll take him apart.”

Rose refuses to be so committal and doesn’t feel his career is in quite the same position.

“I don’t think I can say I’ll definitely retire,” he admitted.

“I’ve said it before and sometimes you can put too much pressure on yourself. I understand why he needs to retire when I beat him. It’s not the same for me, this is my first fight at middleweight and I can rebuild if need be. We’ll have to see, but I’m not even thinking about that.”

Macklin and Rose are two of the nicest men in British boxing and, as it happens, are friends outside of the ring. Indeed Macklin is also close with Rose’s trainer, Bobby Rimmer. Their fight is a fascinating one and, given the circumstances, both are incredibly motivated.

They’ve been cordial, respectful and funny during the build-up and there are plenty of observers who feel it could be fight of the night. Rose agrees.

“I genuinely believe it could be fight of the night. Anthony Joshua’s fight with Charles Martin has stolen the show in the build-up, which is understandable, it’s a world heavyweight clash, but me and Matthew Macklin, I think it helps that we’re friends,” he said.

“It’s a strange one because people don’t know how we’ll react. I promise you, come fight night we won’t be friends and shots will be fired.

“It’s just business. I’ve got two kids that I need to feed, I’ve also got dreams to be a world champion and that is stronger than any friendship. You’ve just got put that aside but we’ll probably go for a pint after.”