They are friends and monumental rivals, and one will need to overcome the other in order to win Olympic gold on the ice at February's Pyeongchang Olympics.
South Korea's Lee Sang Hwa is the two-time defending Olympic champion who now stands between her friend, Japan's Nao Kodaira, and the 500-meter women's speed skating gold medal.
"It (Olympic gold) has been my goal since the start," Kodaira said recently.
Although the 31-year-old Kodaira is nearly three years older, she is now a full-fledged rival, having gone undefeated last season over 500 meters. And as the top women sprinters from East Asia, the two have become close, exchanging letters and presents.
Lee took the speed skating world by storm at the 2010 Vancouver Olympics as a 20-year-old and won world championship titles in 2012 and 2013. In November 2014, however, Kodaira won her first World Cup 500 race, snapping Lee's winning streak on the circuit.
But now, knee trouble and other issues have begun to slow the South Korean down while Kodaira won all 15 World Cup races she entered over 500 meters last season.
"If the Olympics were not being held on home ice, I would have retired," Lee said.
Despite their friendship, Kodaira said Lee does not enter into her thinking.
"I give no thought whatsoever to that (rivalry with Lee)," Kodaira told a press conference at the start of this season. "Every skater exists in a world where what's important is pushing yourself further."