By definition a rivalry is a competition for the same objective or for superiority in the same field, and CT surfing is at its best when driven by fierce rivalries and pumping surf.
Heading into the 2018 US Open, the leaderboard headline is that Lakey Peterson and Stephanie Gilmore, who has her sights set on a record-tying seventh world title, are dominant - winning five of six events this year - and building a significant gap between themselves and the rest of the field.
They're exchanging wins, words and the leader's jersey as a new rivalry develops between the two. Gilmore describes it as, "exciting and beautiful."
And of course, rivalries are nothing new for surfing.
In the late ‘70s, Mark Richards and Cheyne Horan made history as the Wounded Gull took title after title away from Horan. In the ‘80s, the battles between Martin Potter and Brad Gerlach were downright dirty, complete with jersey pulling and board jabbing.
"Years after he and I quit the tour, we ended up talking about how much we hated each other, but how it drove us to be better surfers," explained Gerlach in the lead up to a heritage heat during the 2014 Hurley Pro. "I really hope Pottz has been training for this heat because while the hate maybe gone, I still plan to tear him apart at Trestles."
Come Open season, the classic clashes between Mark Occhilupo and Tom Curren come to mind.
And, of course, the power struggle between Kelly Slater and Andy Irons at the turn of the 21st century stands at the pinnacle of surf rivalries. They barked, they fought, at times they even cried. Sadly, the relationship was cut short with Andy's untimely passing in 2010.
The White Knight and Dark Prince - Slater and Irons on the podium at the 2005 Billabong Pro South Africa. Photo: WSL / Karen
"I am not some bubbly f---ing angel who is going to go out and try to be your best friend," said Irons in a 2008 interview with Surfline.
After winning the J-Bay Open - stop six of the season -- and taking over the gold Jeep leader jersey, Gilmore reflected on her performance, "There was a moment earlier when I got here and opened up a book and it was about J-Bay, and there was a photo of Andy and Kelly and they were holding hands, saying congrats, but they just despised each other."
"So when I paddled out against Lakey," Gilmore continued, "I was like, alright, we both have two wins each, and here we are, so I was going to tap into a bit of that hunger and anger that both Kelly and Andy had."
To date, Gilmore has the edge with three victories to Peterson's two. They've met in two finals. Both times Gilmore has taken the win.
"It's been really fun to battle back and forth with Steph," said Peterson after the final in South Africa. "She's won most of the final match-ups we've been in. I've gotta start winning some of these soon."
So, what does this title race and rivalry mean for the U.S. Open? Will Peterson have a home field advantage? Can Gilmore's elegant performances on point waves translate into success in waist-high Huntington?
"Huntington is a tough place, you know that's Lakey's home turf," said Gilmore. "She feels comfortable in California and I've kind of struggled a little bit in Huntington in the past."
Record-wise, Peterson has the slight edge with an Open title back in 2012. She finished 5th in 2015. In 2016, after sitting out five events due to injury, Peterson finished third. The biggest blemish on her record in Huntington came last year when she finished 13th.
Peterson was raised on the point at Rincon. Gilmore was raised on the point at Snapper Rocks. That might explain why they went first and second at J-Bay. Photo: WSL / Tostee
Meanwhile, historically, Gilmore's been cool and consistent. In 2016 and 2017 she made the quarterfinals for fifth-place finishes. In 2014, she was runner-up and less than a point away from beating Tyler Wright to take the win.
Stats are helpful and informative, but rivalries are built on passion.
Slater was the white knight in the white wetsuit. Irons prided himself on being the dark prince, the man in the black wetsuit.
In the case of Gilmore vs. Peterson, the Aussie vs. American aspect is in play, but for the most part, their rivalry is performance-based and resides solely in the lineup.
Gilmore enroute to her third 2018 tour victory with style to spare. Photo: WSL / Tostee
"You can never really feel like you're comfortable at the top," says Gilmore. "I've never really felt like, yeah, I've got this in the bag."
This weekend is forecasted to be classic Huntington conditions - waist-high and on-shore - so it's going to be a massive test for both Gilmore and Peterson.
Who knows, maybe they'll meet up in the final and battle it out again, a circumstance for the fan that presents no middle ground: you're either on one side or the other, so pick one and cheer your heart out.