Grotheer, who claimed the gold medal at the Beijing 2022 Winter Olympics, topped the standings after two runs in front of compatriot Axel Jungk.

After the first run, he was tied with Jungk, but behind South Korean Jung Seung-gi by 0.06 seconds.

China's Yan Wengang was tied with the Germans too.

However, Jungk capitulated in the second run, ending up with the slowest time of the 20 qualifiers to move down to 13th.

Grotheer had a strong second effort to finish in a combined 1min 54.32sec, with Jungk second, 0.39 seconds off the winner in second.

Britain's Matt Weston came close to splitting the home favourites, finishing 0.40 behind the gold medallist, for the bronze.

His team-mate Marcus Wyatt was fourth, followed by Yan.

Bos was consistent across two runs in the women's skeleton, to inch in front of Canadian Mirela Rahneva by 0.06 seconds, with a best total of 1min 57.18sec.

Having a best result of fifth before today, last year's World Cup champion and Olympic bronze medallist was second-quickest on both efforts, while Rahneva's second was only fifth fastest.

It meant four sliders have won the opening four races of the season, with Rahneva victorious in Park City, and Germans Hannah Neise and Tina Hermann winners in Whistler and Lake Placid respectively.

Neise finished third today, 0.16 behind the winner, and just 0.06 in front of Hermann.

Austrian Janine Flock was half-a-second off the pace of Bos in fifth.