The middleweight pair’s first fight, in September 2017, was controversially scored a draw, with Golovkin landing more punches and considered the stronger fighter by many pundits.
“I hope it is going to be a better fight than the first one,” said the 36-year-old Kazakh.
A May rematch was postponed after Alvarez, 28, failed two drugs tests.
The Mexican blamed his positive test for clenbuterol – an asthma medication that can also help build muscle and burn fat – on eating contaminated meat.
The drug is sometimes illegally mixed into livestock feed to make meat leaner.
Alvarez has lost just once in 52 fights – a points defeat by Floyd Mayweather in September 2013 – while Golovkin has won 38 of his 39 contests.
“I strongly feel both guys need each other to cement their legacy,” said promoter and former multiple-weight world champion Oscar de la Hoya.
“‘Canelo’ has to go out there and get the knockout to cement that legacy and be the pound for pound best fighter on the planet. It is vice-versa for GGG – he has to go out there and win decisively.”
‘Canelo is angry’
Saturday’s bout – which will be in the early hours of Sunday morning in the UK – will be broadcast live from Las Vegas’ T-Mobile Arena on BBC Radio 5 live, with a live text commentary on the BBC Sport website and app.
The first meeting between the pair proved a gripping contest, with judge Adalaide Byrd controversially awarding Canelo 10 rounds of a bout many ringside observers thought he had lost.
Since the tie, each fighter has spoken derogatorily of the another, with Golovkin unhappy at Alvarez’s excuses for his failed drugs tests.
De La Hoya told BBC Sport: “For the first time I am hearing ‘Canelo’ angry. He has trained angry, he wants to fight angry. He wants to go out there and knock him out.”
Analysis – ‘No fight brings as much class’
BBC Sport boxing commentator Mike Costello
No match-up in the world of boxing right now could bring this much class and so many factors to a single ring.
The draw was controversy, as were the two failed drug tests for Alvarez. There will be skill, power, guile, resilience, pedigree and rivalry added to that controversy on Saturday night.
BBC Radio 5 live boxing analyst Steve Bunce
Last year it was the fight that would save boxing after the McGregor v Mayweather bout, when people said the lunatics had taken over the asylum.
They put on a fantastic spectacle, it was gripping and you couldn’t take your eyes off it. I still think Adalaide Byrd’s score is the worst single score that I have seen in my time in this business.