Leading Russian pair Alexander Zubkov and Alexey Voevoda lead the Winter Olympics two-man bobsleigh standings at halfway, with Jamaica in last place.
The host-nation favourites finished in a combined time of one minute 52.82 seconds to lead Swiss duo Beat Hefti and Alex Baumann by 0.32 secs.
"Alexander Zubkov is the star of the Russian team, but he and Alexey Voevoda absolutely hate each other. They don't talk but somehow they have got it together in time for the Olympic Games and they are in gold medal position now."
Great Britain's Lamin Deen and John Baines
finished the day in 23rd place.
Jamaica, appearing in bobsleigh at the Winter Olympics for the first time since 2002, were last in 30th.
Winston Watts, 46, was part of Jamaica's bobsleigh teams in 1994, 1998 and 2002, and this time teamed up with brake-man Marvin Dixon.
Watts had to contend with almost snapping off his helmet visor at the start of his second run, saying: "It's just one of those things.
"I pulled my visor and with all the adrenaline it just broke, and I said: 'Well, I'm not going to stop now, I'll show the world I've got heart and I'll take my sled down.'"
Asked about regular comparisons to the film 'Cool Runnings', featuring a Jamaican bobsleigh team, Watts added: "Cool Runnings is a very nice movie and it opened such a nice way for us, but a lot of people look at that movie and see us as jokers.
Jamaica are last after the first two runs but insist they are here to compete
"We're not jokers - we're serious contenders. This is not an excuse but things didn't go the way we wanted them to. But we have come here and we have gone out to compete the best we can and to show the world that we're still alive."
Competing 50 years to the day that Tony Nash and Robin Dixon won Olympic gold for Britain, the current GB pair of Deen and Baines know that finishing in the top 20 would be an impressive achievement.
Baines was only drafted into the two-man set-up last week following a career-threatening
injury to former Olympic sprinter Craig Pickering.
"We haven't had long to prepare and still have a few things to work on, but I'm sure we'll be going quicker tomorrow," Deen told BBC Sport.
The third run will begin at 1430 GMT on Monday. Only the top-20 sleds after that stage will be allowed to compete in the fourth and final run.