Great sport is defined by its rivalries - the more intense and sustained they are the more compelling the contest - and two of the world’s leading mountain bikers have turned the 10 editions of the Cape Epic into their personal battleground: Christoph Sauser and Karl Platt.
Both are moving towards the twilight of their competitive years and this month both have an extra motivation to win the world's foremost mountain bike stage race again: to become its first five-time winner.
German Platt won the first Epic in 2004, when it was raced between Knysna and Cape Town, with Namibia's Mannie Heymans. He did it again in 2007, 2009 and 2010 with countryman Stefan Sahm.
Sauser won with fellow Swiss Silvio Bundi in 2006, with Burry Stander in 2011 and 2012 before the South African died in an accident while training, and with Czech Jaroslav Kulhavy in 2013.
In person, Platt is affable, charming and laughs easily, while Sauser appears reserved, considered and thoughtful. The German says he is "addicted to fast cars", while Sauser lists reading and following the news among his off-the-bike activities.
Then they get on their bicycles, where their approach to racing suggests different aspects to their personalities. Platt's Epic wins have generally been built on patience and attrition, while Swiss Sauser acknowledges that his races have been "pretty much all or nothing" - winning or DNF (did not finish) thanks to crashes, illness or "some drama".
Sauser's pedigree is unquestionable. Besides his Epic wins, he is a former cross country world champion, Olympic medallist and goes into the race this year as the reigning marathon world champion (a title he'll defend in Pietermaritzbug in June). But the Epic is raced in teams of two, and this year he will be riding with a partner who has relatively little mountain biking experience: Team Meerendal Songo Specialized will consist of Sauser and František Rabon, a former road racing professional who has switched to mountain biking relatively recently.
Sauser is confident though that Rabon has the "reliability, toughness and strength" he looks for in a partner. He is also an experienced stage racer - he has competed in the Giro d'Italia and European Classics - and has what his fellow pros call a big engine: "In intervals I don't have a chance against him," said Sauser.
Team Bulls' Platt is riding with fellow German Urs Huber - the same partnership finished second last year - and both have been showing excellent form in recent races.
"Urs is in incredible shape," said Platt. "We're pretty confident and motivated. For sure I want to be the first to have five wins, but it won't disappoint me if I don’t win it five times."
"I'm in good shape. Last year I was getting burnout so from August I took two-and-a-half months off - lots of beer and wines," he said, laughing.
Sauser says he is at his best on long stages. "That's where I get the adrenaline - towards the end". After the 23km prologue on March 23, four of the seven stages are more than 100km. The 134km stage three and 110km stage five could prove decisive - the latter contains a huge 2,900m of vertical gain. The final stage is the relatively short 69km stage seven from Elgin to Lourensford Wine Estate, Somerset West.
Platt will be hoping his particular gift is paying off by then. "I'm not a perfect climber but I have technical skills on the climbs and downhills. If I am in good shape I get stronger and stronger in stage races."
Both are over their "base training" periods and have been concentrating recently on intervals and racing - fine-tuning themselves for the Epic.
And both paid tribute to the Epic's role in growing mountain biking and the now international status of the event.
"It would be interesting to see where South African mountain biking would be without the Cape Epic," said Sauser.
Platt said, "It's got better and better and there is great coverage all around the world. It is the biggest [mountain bike] stage race in the world and the best organised. With all the media coverage it is very special."
He also believes the race has helped change mountain biking around the world. In South Africa the change is marked: "In the Western Cape now there are trails everywhere - the best trails ever."
"It's funny to see the 2004 videos - how crazy we were on 26-inch bikes (nowadays just about everybody rides the bigger-wheeled 29ers), and hardtails (as opposed to the double suspension bikes preferred by most of the top pros now) - we looked completely kak," said Platt.
Sauser points out that the event has become far more competitive over the years, and therefore much tougher: "We used to race for the last hour-and-a-half of the stage. Now you are fighting for position from the first minute."
That fight - through the dust, mud and rugged trails of the Western Cape - will be marked this year by the personal ambitions of two of the toughest riders on the planet.