GANGNEUNG, South Korea (AP) — The tension was thick. The mood was glacial. And the siblings were sparring.

"Hey, Becca. Come here," American curler Matt Hamilton said to his frustrated sister, whose stone had just glided past its intended target. "Don't roll your eyes at me."

That eye roll turned into crossed arms, which turned into Wisconsin's beloved brother-sister curling duo standing far apart on the Olympic ice, leaning on their respective brooms and diligently avoiding eye contact. Had it happened in just about any other sport, this fleeting spat during Sunday's Olympic mixed doubles match would have gone unnoticed by the public. But in curling, every player wears a microphone.

And what fans get is a uniquely intimate view of the athletes as all their banter, bickering and baffling strategy-talk is carried across the airwaves to viewers worldwide.

In some ways, curling is the closest the Olympics comes to reality TV — which may help explain some of its cult allure to people watching at home.

"I feel like I'm best friends with @MattJamilton and @heccabamilton because I've spent so much time with them the last couple of days. Watching curling has become my life!!" one of the Hamiltons' fans wrote on Twitter as Sunday's game rolled on.

Even when no one is fighting, half the fun of listening to curlers is trying to decipher what they're talking about. And with four games played simultaneously during Sunday's mixed doubles round robin, it's understandable if uninitiated viewers got a little confused.

"Hack weight, hack weight," Canada's John Morris said to his teammate Kaitlyn Lawes.

"Think you want to stay on the nose," she replied.

"Yep, you betcha," Morris concurred.

Let's break that down: Morris wanted to throw the stone with enough momentum to reach the hack, those black push-off blocks on either end of the ice. Hitting a rock on the nose means hitting it straight on so the shooting rock sticks in place.

Got that? Good. What followed was a string of orders from Morris as Lawes began sweeping. "WHOA, WHOA, WHOA, WHOA, WHOA! CLEAN, CLEAN! WHOA! WHOA! YUP-YUP! HARD, HARD, HAAAAAARD!"

If you watch curling, you need to know these ubiquitous terms: "Whoa" means to stop sweeping. "Clean" means to lightly clear the ice of any debris in the rock's path. And "HARD" means sweep as vigorously as you can.

Back on the U.S. vs. Finland ice sheet, the Hamiltons had put the drama behind them. "WHOA!" Matt called to his sister, who was sweeping. "Line's good! Switch. Yup. HARD! Becca, GO!" The rock coasted to its intended spot, earning a compliment of "Beautiful" from Becca. "That's pretty good!" Matt agreed.

Finland called a time out. It was their last throw of the game and they were up 7-3. If they missed the shot, however, the Hamiltons had a chance to tie it up as they had three rocks in the house with one rock left to throw. Finland's coach Brian Gray ambled over to strategize.

"It's quite obvious what we're going to do," player Tomi Rantamaeki said.

"Is it?" Gray replied, speaking for most of the viewing public.

What followed was a discussion of fast ice, playing the peel and looking for "anything between 10 percent and 50 percent on the side," none of which was likely to make anything obvious to the vast majority of viewers. But what mattered was the result: Oona Kauste threw the stone and it knocked one of the Americans' rocks out of the target, giving Finland its first round robin win, and prompting a congratulatory handshake from the Hamiltons.

Meanwhile, things were going swimmingly for Canada, as evidenced by the plethora of "Good shot" and "Nice scrub" compliments flowing between the teammates. And when it was over, after the Canadians had secured a 7-3 victory over Korea, shaken their opponents' hands and waved appreciatively to the crowd, the microphones picked up Lawes discussing the less glamorous side of being an Olympian.

"Well," she said. "I'm sweaty."