The intense rivalry between Mike Alvarado and Brandon Rios is one of the biggest in boxing right now.

Brandon Rios v Mike Alvarado

They meet in a rubber match in Denver on Saturday night and promise BoxNation viewers another thriller.

Rios won their 2012 Fight of the Year in seven madly exciting rounds, but the following year in another memorable clash, Alvarado got revenge.

The fight should be another classic, sure to be remembered as one of boxing's most famous trilogies.

We look at five other modern-day, three-fight rivalries that captured worldwide attention.

Muhammad ALI v Joe FRAZIER
It was sport's greatest ever rivalry. They met in the Fight of the Century at Madison Square Garden in March 1971. Frazier was unbeaten in 26 and Ali had won all 31.

It was a stunning fight and Frazier retained his heavyweight title 9-6. 11-4 and 8-6-1. Ali was floored in round 15 but survived. Ali earned revenge in a non-title bout at the famous New York venue in January 1974, winning a narrow verdict over 12 rounds, although some dispute the verdict.

Their differences were settled in the 'Thrilla in Manila' - one of the most iconic sporting events ever. It was one of the best battles ever seen. The turning point came in round 13 when Ali badly hurt Frazier and landed many unanswered punches.

Trainer Eddie Futch had seen enough at the end of round 14 and pulled Frazier out. Frazier protested stopping the fight, shouting "I want him, boss," and trying to get Futch to change his mind. Futch replied, "It's all over. No one will forget what you did here today."

Muhammad Ali v Joe Frazier

Marco Antonio BARRERA V Erik MORALES
Undoubtedly the greatest rivalry in Mexican boxing history and the bitterness between them continues to this day. Morales took a split decision in the first clash, which was Ring Magazine Fight of the Year in 2000. It was one of the finest ever.

Barrera got revenge in a Las Vegas rematch, surviving a knockdown to win a unanimous decision to claim the WBC Featherweight crown. Barrera won a majority decision in 2004, in another Fight of the Year.

Eric Morales

Arturo GATTI v Micky WARD
What a rivalry between two men who fought three times between May 2002 and June 2003, delivering three searing battles and 30 brutal rounds where both men went through the pain barrier. Ward won the first fight that was Ring Magazine's Fight of the Year, getting the nod when a ninth round knockdown made the difference.

Less than six months later they met again and Ward was dropped in round three, but survived as Gatti got the nod in another wild fight. After the third fight, which was 2003 Fight of the Year, both men ended up in hospital for a check-up.

It was X-rated and perhaps Gatti was saved by the bell in round six, after being dropped. Gatti recovered brilliantly though and got the decision.

Ward v Gatti

Riddick BOWE v Evander HOLYFIELD
What a three-fight act this was. Bowe never truly lived up to the potential expected, but his performance in the first fight that he won on points was awesome. Bowe took the fight and the world heavyweight title on points.

The tenth round was one of the best three minutes of heavyweight action ever. Holyfield got revenge over 12 rounds and won back the title in another fight where the pendulum swung.

Mid-fight, one of the most bizarre incidents ever occurred, when fan-man, James Miller gate crashed the ring on a parachute. The third fight in November 1995 didn't go the distance, when Bowe won in eight rounds despite being dropped for the first time in his career during round six.

Riddick BOWE V Evander HOLYFIELD

Muhammad ALI v Ken NORTON
They met twice in 1973. Ali was a 1-5 favourite for the first fight on March 31 in San Diego, but suffered a broken jaw in round 11 and dropped a split decision. Six months later Ali took a split decision in a hard-fought battle where both men landed heavy punches.

When Ali faced his old rival in a world heavyweight title defence in September 1976 at Yankee Stadium, New York, he took a belting but clung on to take a close unanimous decision after 15 rounds. Many people believe that contest was the start of Ali's decline.