Five biggest heavyweight upsets in modern boxing history

Former world heavyweight boxing champion Anthony Joshua is looking to avenge his shock defeat to Andy Ruiz this weekend. Here are five of the biggest upsets to shake up heavyweight boxing.

Muhammad Ali beat George Foreman
KO round eight

Boxing history is littered with iconic moments but the Rumble In The Jungle, which saw underdog Muhammad Ali overcome tremendous odds to beat heavyweight champion George Foreman, is undoubtedly the most famous fight of all time.

Immortalised in Oscar-winning documentary When We Were Kings and a host of boxing books, the fight took place in Kinshasa, Zaire on October 30, 1974 against a backdrop of political unrest and human rights protests.

More on the big fight

• Ruiz v Joshua 2: big-fight preview and prediction
• Ruiz v Joshua undercard
• The greatest heavyweight rematches

Reports claim Ali was anything between a 4-1 and 49-1 underdog that night, but was isn't in doubt is that Foreman was a huge favourite and most experts had him winning easily after an impressive KO streak which included wins over Joe Frazier and Ken Norton.

But Ali won the hearts and minds of the oppressed Zaire locals and inspired by chants of "Ali Bomaye", implemented his infamous 'rope-a-dope' tactic of covering up until power-puncher Foreman ran out of energy.

It worked a treat, and when Foreman ran out of steam in the eighth round Ali suddenly sprang out of his defensive shell, spun him around and knocked him out.

Leon Spinks beat Muhammad Ali
Split decision after 15 rounds

Muhammad Ali was on the receiving end of a huge upset in 1978 when his title was taken by Leon Spinks in a defeat which turned out to be the beginning of the end of his legendary career.

Ali had won his previous 14 fights and few people predicted that his reign was about to come crashing down. Spinks, a 10-1 underdog in the Las Vegas casinos, had only had seven pro fights and became the most inexperienced boxer ever to win the world heavyweight title via a split-decision victory after 15 close rounds.

"My rope-a-dope didn't work", Ali said after the fight. "He was too strong."

Ali's trainer Angelo Dundee added: " I prepared myself for this day for a long time. I conditioned myself for it. I was young with him and now I feel old with him".

Ali won a rematch on points later that year in what would be his final victory in a boxing ring.

Hasim Rahman beat Lennox Lewis
KO round five

In a situation not unlike the one that saw Anthony Joshua failing to agree terms with Deontay Wilder, the two biggest heavyweight names of their generation - Lennox Lewis and Mike Tyson - had also failed to agree terms to fight, and so Lewis took on unfancied contender Hasim Rahman in South Africa in April 2001.

Lewis was a massive 1-20 favourite for victory in his 15th world title fight, and had been unbeaten for six years since a previous shock defeat to Oliver McCall.

But victory at heavyweight cannot be taken for granted and he was made to pay for some sloppy preparation. The fight was at altitude - 5,200 feet above sea level - and Rahman had arrived several weeks before so his body could adjust, but Lewis was busy filming Hollywood movie Ocean's Eleven and left it late to make the trip.

He weighed in at his heaviest ever for a fight and looked to be breathing heavily early in the fight. He was loading up, looking for big punches, but when one landed it was on the chin of the champion, and despite Lewis getting up off the canvas the referee waved off the fight.

Lewis called for an immediate rematch and beat Rahman in four rounds later that year, which will give Joshua confidence for his rematch with Ruiz.

Andy Ruiz beat Anthony Joshua
KO round seven

On the face of it, there can be no unlikelier upset in combat sports history than than self-proclaimed "chubby little fat kid" Andy Ruiz toppling the Olympic golden boy and undefeated world heavyweight champion Anthony Joshua,

AJ's body looked like it had been cut from the finest marble, while Ruiz looked like a dough ball. And even though a handful of people in the know, such as Ruiz's former trainer Freddie Roach, warned not to write him off, few doubted what their eyes were telling them - that Joshua was too big, too strong and too fit to lose to this Snickers-loving stand-in.

Odds of 30-1 had been chalked-up by some bookies on fight night with Ruiz lined up as a late replacement on three week's notice as Joshua's original opponent Jarrell 'Big Baby' Miller failed a drugs test, yet few took the bait.

But looks can be deceiving. From the first bell Ruiz went on the offensive, taking centre-ring and pushing Joshua on to his back foot.

Normal service seemed to be resumed by the third round when Joshua knocked down Ruiz, but Ruiz got back up and caught Joshua with a big punch of his own as AJ rushed in looking for the finish, and toppled him again at the end of the round.

AJ never recovered and was knocked down a twice more in the seventh, spitting out his gum shield and turning his back on the referee, who waved off the fight, sparking accusations that Joshua 'quit'.

James 'Buster' Douglas beat Mike Tyson
KO round ten

When the 'Baddest Man on the Planet' Mike Tyson lined up to take on James 'Buster' Douglas in Tokyo in 1990 it was seen as nothing more than an exhibition and Douglas was a massive underdog with the bookies, but what transpired will be forever remembered in sports betting history.

Only 23 days earlier, Douglas had to deal with the death of his mum, but he turned that heartache into inspiration to ensure that his name is always the first to pass the lips of boxing fans conjuring memories of monumental upsets.

According to boxrec.com, Jimmy Vaccaro, who ran the race and sports book at The Mirage Hotel & Casino, said: "Nobody thought Douglas had a chance. So the question was, 'What do you make the line?' My initial instinct was to make it 12-1, but I realized we'd get killed with Tyson money. So I made it 27-1.

"Right away, someone bet $54,000 to win $2,000, so I upped it to 32-1. A guy from California comes in and bet $93,000 to win $3,000. I can’t find anyone willing to take Douglas. So now, I make it 37-1, and it stayed there for a while. I think one guy bet $1,000 on Douglas.

"Now it’s three weeks before the fight, and I said we’re going to 42-1. The night of the fight, it’s still 42-1."

There were widely reported stories of Tyson not taking his training seriously but hardly anyone took any notice, and Douglas controlled the fight from the start. Tyson struggled to find his killer instinct, but looked to have got out of jail when he floored Douglas in the eighth, only for Douglas to get back up and finish an exhausted Tyson in the tenth.

Despite Douglas outscoring Tyson by landing 230 total punches to Tyson's 101 on the Compubox fight stats, one judge had Tyson winning while another had it even at the time of the stoppage, which suggests Douglas would have been stitched up if it went to the scorecards - a mega-money showdown had already been agreed for Tyson to face Evander Holyfield in his next fight, but that ended up being put on ice for another six years.

In heavyweight boxing, the only thing that is certain is that anything can happen.

Today's top sports betting stories

Follow us on Twitter @racingpostsport

Like us on Facebook RacingPostSport