Canelo Alvarez and Gennady Golovkin's mega-money rematch was one of boxing's highest-profile events in the modern era.
But the lucrative showdown was marred with controversy surrounding the incredible spectacle, which lit up the hallowed walls of the T-Mobile Arena in boxing capital Las Vegas.
Prior to their rematch, Golovkin and Alvarez had fought out to a draw in their first battle in one of the most controversial scoring decisions in boxing memory.
Most believed Golovkin had done enough to win, but he was forced to settle with the chance to get his revenge in a captivating sequel.
Canelo fails drug test before Golovkin rematch
After his draw with Golovkin in September 2017, an immediate sequel was being plotted.
However in a huge scandal, it was revealed that Alvarez tested twice positive for banned substance clenbuterol, which saw him handed a six-month suspension.
The Mexican superstar denied deliberate wrongdoing, insisting it was caused by contaminated meat.
But it added another layer to an already spicy rivalry with Golovkin fuelled by the controversial decision from the first fight.
Canelo edges Golovkin in blockbuster rematch
Nonetheless, the sequel was agreed in a huge fight which saw the pair earning millions in lucrative fight purses.
Canelo's failed test added another layer to a tense build-up with many fancying Golovkin to storm away and finally claim his victory.
But the showdown, which generated a blockbuster $117million in revenue on American shores, didn't play out as many expected.
Alvarez was far improved and had more positive signs despite Golovkin establishing himself from the first bell.
The pair's contrasting styles made it a minefield to score with Alvarez responding with counter punching in spells to his rival's aggression.
An epic final half of the fight saw it viewed as a barnstorming classic, with both fighters having their own positive spells.
'GGG' had the most eye-catching moment in the fight, with a booming right hand wobbling Alvarez but he recovered well.
He was fatigued but the pair slugged it out until the final bell, with the boxing world's verdicts all over the shop.
But once again, Golovkin was denied on the judges' varying scorecards, which judged Canelo as the narrow victor and saw him snatch his world titles.
It saw Alvarez cement his name as the sport's pound-for-pound number one.
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And it saw the Kazakh KO artist lose for the first time in his career, halting a 12-year spell in the professional ranks where he was never conquered.
Golovkin storms out of ring in rage
Of course, the decision was once again met with contention from the global boxing community.
Golovkin himself refused to immediately address the decision and stormed from the ring, skipping his post-fight interview.
Alvarez himself acknowledged how close the encounter was in his own post-fight assessment.
But it was no consolation for the beaten former champion, who felt aggrieved once again.
How the Canelo vs Golovkin rivalry ended
Years on from their controversial rematch, the pair met again but with Golovkin years beyond his physical prime in a trilogy in 2022.
And finally the rivalry got the emphatic conclusion it warranted, with Golovkin beaten in a dominant and one-sided display by Alvarez.
It was a sad end for the Kazakh but the pair finally let bygones be bygones and ended on better terms.
Golovkin and Canelo remain two modern era legends and their rivalry still remains a talking point until this day.
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