Canada 2 wrestle the lead from Germany 2 with a time of 55.38. Two to go, and then the Brits. Time to take your seats.

More from GB bobsleigher Paula Walker on her partner John Jackson: "I think he is still trying to find redemption from 2010 (when he crashed in the four-man competition) and after this Olympics is out of the way he can look at what happens next.

"He has a great future and with equipment and crew he could have a few good World Cup seasons in him - so you never know (Jackson could do another Olympics.)"

USA 2 take the lead from Canada 1 with 55.64 after a good drive by Nick Cunningham.

GBR 1 pilot John Jackson led a four-man crew to a fifth-place finish at the 2013 World Championships, ending just 0.07 seconds adrift of a medal. His four-man bob also secured the first World Cup medal by a British men's team since 1997 when they claimed silver at Lake Placid in December 2013.

Russian prime minister Dmitry Medvedev has just arrived with a vast entourage to ramp up the pressure on the Russian athletes. Latvia 2 produce a slick and rapid 55.81 to take the early lead. Just 14 crews to go with the Brits racing six from the end.

Great Britain bobsleigh pilot Paula Walker, who is GBR 1 driver John Jackson's partner, has been speaking to BBC Sport's Nick Hope between the third and final run of the four-man competition.

She believes Jackson could sneak a bronze medal today, but is finding watching difficult.

"It's worse watching John than being at the top myself as I have no control over what he does," she says.

"I haven't done enough practice watching him not to be nervous. He had a really good clear drive I think if he can repeat that he can jump into that third position.

"I asked if he was tired this morning and he said 'I'm ready'."

Colin Bryce
Former GB bobsleigher on BBC TV

"I do fear for this track. The ice is so warm. That was a monster start by GB2 - definitely world-class."

Image source, AFP

Lamin Deen gets GBR 2 off to a great start, but they can't quite maintain the pace and have to settle for a time of 55.95 - their third best out of the four runs. They are quickly usurped by the Italians, who post 55.88 to take the early lead. Remember, we are building to a crescendo here with the competition-leading Russians set to go last.

Lauren Binks:, external Seriously, why would you choose cross country skiing?! Spend more time skiing up the mountain than down it! Too much effort.

Amy Williams
2010 Olympic skeleton champion on BBC TV

"All the crew come out with helmets on because their breath can fog it up otherwise. A lot of the bob boys cut off their trousers - I think it is more aerodynamic but they also like to show off their calf muscles!"

Five minutes to go then until the final run of the men's four-man bobsleigh. Alexander Zubkov claimed Russia's first Olympic bobsleigh gold in the two-man on Monday, and now the 39-year-old is in prime position to double up. Latvian pilot Oskara Melbardia and the USA's Steve Holcomb may have something to say about that.

Image source, Getty Images

Russian Alexander Legkov, who won gold in the men's 50km cross-country race, said of his medal. "This is priceless. It's more valuable than my life, I can't express how I feel. For 15 years I've been trying for this result."

Brent Pope
BBC Sport ice hockey commentator

"Canada have won most gold medals of any nation in ice hockey. I'm a bit surprised in the manner in which they got here - they did it with defence rather than offence. The Swedes have great quality, though, and they deserve to be in the final."

Ross:, external Best moment of the Games, the Canadian women's ice hockey team turning it round in the last three minutes of the final.

Amanda Oliver:, external Loving my last weekend of random snow/ice sports. A #bobsleigh breakfast. What am I going to do next weekend?

Jack Weightman:, external My favourite moment was David Murdoch's final shot of the quarter-final. I was in work watching iPlayer and I jumped out of my seat.

Canada 3, who suffered a horrible crash when in eighth position yesterday, prove their class with a run of 55.72, the tenth best performance of the day. But the time they lost yesterday means they will not qualify for the fourth and final run.

There will, however, be two British teams in the final, with GBR 1 in sixth and GBR 2 in joint 18th.

Nick Hope
BBC Sport in Sochi

"Massive security operation here today, we're expecting President Putin to arrive later for what he hopes will be a Russian four-man bobsleigh gold.

"Our live broadcasting position for presenters has been blocked today - by snipers!

Image source, AP

"Rumour has it that Putin personally asked pilot Alexander Zubkov to come out of retirement for these Game and it's certainly paid off so far after he won two-man gold last week and as I say is on course for further success today."

Team GB skeleton star Shelley Rudman:, external Think it is fair to say that the final runs for everyone watching John Jackson and the GB crew later will be *edge of seat time*!

The Japanese sled is all over the track, mounting the walls and taking some hefty blows to the front wing. I just hope they are fully insured!

Amazingly, the team's time of 56.63 is only 1.61 secs behind the table-topping Russians. The margins in this sport are absolutely tiny.

Image source, Getty Images

Britain's Andrew Musgrave, competing in his second Winter Olympics, who finished 53rd in the men's 50km cross-country race this morning: "I didn't feel so great, I am little bit ill, I had a bit of a fever last night.

"But I thought I may as well race. It is the Olympics and it comes around once every four years and it might have gone well.

"In the Tour de France guys race with broken collarbones, if I have only got a sore throat and a cold I just thought 'I may as well just go'."

It's looking very good for Lamin Deen's GBR 2. They remain joint 18th, and such is the time difference that only a miracle could see one of the stragglers force they way into the top 20.