So Anthony Joshua is fighting American Andy Ruiz tonight, but even that was not the original plan.

He had been scheduled to face another American, Jarrell Miller, but that fell through after Miller was denied a licence to fight following an "adverse finding" in a drug-testing sample.

That left Joshua's promoters Matchroom Boxing with the task of coming up with a credible opponent at short notice.

Andy Ruiz made lots and lots of noise on social media, got the attention of promoter Eddie Hearn and the fight was made.

Croydon's Joshua Buatsi cruised to victory over Marco Antonio Periban after the referee stepped in during the fourth round.

The 26-year-old Brit looked comfortable throughout as he claimed victory in only his tenth professional fight.

Image source, Reuters

Already tonight...

Chris Algieri beat Hull's Tommy Coyle to retain the WBO international super-lightweight title after the Brit's coach stopped the fight at the end of the eighth round.

Image source, Reuters

So that's our early debate before things heat up in the 'Garden'.

Anthony Joshua, Deontay Wilder, Tyson Fury? Who is the better fighter and why?

Tweet us using the hashtag #bbcboxing and we will post your words of wisdom in this page throughout the wee hours.

No heavyweight fight is ever "officially on" until they are both in the ring, but who knows, Wilder and Fury both win their next fights and meet in December, Joshua wins tonight and then the two winners fight next year in Vegas? Sounds simple.

It won't be that simple, but here's hoping.

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Well, there have been some potential developments to maybe get excited about earlier on Saturday...

WBC world heavyweight world champion Deontay Wilder says he has signed an agreement to face Tyson Fury in a rematch after he has fought Luis Ortiz.

Wilder, 33, tweeted on Tuesday he had agreed a rematch with Ortiz, which is expected to take place in September.

Now he says a repeat of his December draw with Fury, 30, would follow his fight with the Cuban.

"All contracts have been signed already," he tweeted. "It's officially on. As I always say I'm the realest champion in the business and as I've mentioned before I must handle all my controversial fights ASAP.

"By no means am I looking past Ortiz. He's a dangerous fighter but I am looking through him."

So, what's going on here then?

Why is Anthony Joshua fighting someone who you may never have heard of? Wasn't he meant to be fighting Deontay Wilder, or Tyson Fury, or even Dillian Whyte.

Well, yes, yes and yes. But nothing is ever straightforward in the world of boxing politics. Last year it looked simple, Anthony Joshua versus Deontay Wilder for all the heavyweight belts.

They even had a potential date in April reserved at Wembley Stadium to see who would become the undisputed champion. But no deal could be done, then Wilder and Fury fought out a classic, and hugely controversial draw, and then Wilder, Fury, Joshua all became signed to rival television networks in America and the fights we have been craving have not happened.

Luke Reddy
BBC Sport at Madison Square Garden

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If you’ve never been to Madison Square Garden let me paint a picture.

Pennsylvania Station runs underneath it, so there’s general chaos outside 24 hours a day. You can get trains from that station to major cities, so it’s lively.

There’s a general scent of something being smoked in the air and the road outside is - like many here - a lesson in timing for the pedestrian.

If shopping is your thing, department store Macy’s is over the road. You’ll get lost in there without fail.

And if you’ve not had enough mayhem in your day, you can walk straight up Seventh Avenue to Times Square (below). There you’ll find more mayhem and people dressed up as Super Mario, Buzz Lightyear and The Joker. They’ll want a couple of quid off you to pose for a picture though.

In a nutshell, this is a stretch of road where you’ll see pretty much everything.

If you want an easy life, just take a seat in the arena and watch boxing, concerts, ice hockey side New York Rangers and basketball outfit New York Knicks.

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These are the main fights that we will be focusing on tonight.

In terms of a rough schedule, we're looking at Katie Taylor's ring walk at 01:40 BST ish, then Callum Smith at about half past two and Anthony Joshua is expected from 03:30 BST.

So, basically, there is no point going to sleep. Throw an all-nighter.

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You quite simply don't want to miss this epic night of boxing!

Michael Emons here and it's my pleasure to be guiding you through a huge night of boxing coming to us from Madison Square Garden.

The main event is Anthony Joshua versus Andy Ruiz and we also have full text and radio coverage of Katie Taylor's fight as she looks to be a unified champion and also Callum Smith's WBA Super world title defence as well.

Olympic champion...

Image source, Getty Images

... undefeated heavyweight champion...

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...what a boxing career Anthony Joshua is having. And tonight he gets to put his belts on the line at one of the most iconic venues in boxing.

Image source, Getty Images