Yun's home-ice advantage is an important part of this Olympic story, though it's not why he's winning. He wins everywhere. He toyed with the World Cup circuit this season, winning five times and finishing second in his other two starts. He won the overall season points total even after skipping the final race to prep for Pyeongchang.

Latvia's Martins Dukurs is third at the midway point, 0.88 seconds off the lead.

"Really simple. I made less mistakes in the second run," Dukurs said. "This track is tricky. We'll see. I'm not under any pressure."Britain, which made a splash before the event with news of some high-tech uniforms that had other competitors questioning their legality, was led by Dom Parsons and his fourth-place showing after the first two runs.

Parsons said every team is chasing technological edges, and he thinks the British have tinkered smartly enough with speedsuits and sled setups to be in the medal mix.

"It's not a huge margin," Parsons said. "It's just all the little hundreths everywhere that hopefully add up."

AP