Great Britain's team pursuit line-up of Bradley Wiggins, Andy Tennant, Owain Doull and Steven Burke missed out on claiming a medal at the opening round of the UCI Track World Cup in Cali, Colombia, after finishing in fifth place.
The team qualified fourth fastest behind Russia, Switzerland and Australia, which meant they faced Russia in the first round.
The Russian team of Viktor Manakov, Sergey Shilov, Dmitry Sokolov and Kirill Sveshnikov beat the British line-up - which included Jon Dibben instead of Burke during the round - by 3-59.315 to 4-00.629, relegating the Brits to face Germany in the ride-off for fifth and sixth place.
Although GB subsequently caught Germany to take fifth place, it will be a bitter blow to the team's preparations ahead of the 2016 Olympic Games in Rio - particularly as they looked on great form during their recent European Championship victory.
Russia went on to win the men's team pursuit overall, with silver going to Switzerland and bronze to Australia.
GB women's team pursuiters down to three
Illness reduced the Great Britain women's team pursuit squad to just three riders in their race for bronze, after they failed to make it through to the gold medal final.
Rules stipulate that squads have to start with four riders, so an unwell Elinor Barker lined up for the start but then swung off leaving the trio of Joanna Rowsell Shand, Ciara Horne and Katie Archibald to take bronze against China.
"She [Barker] has been feeling a bit unwell," Rowsell told the British Cycling website. "But the regulations say that although you can finish with three you can’t start with three so I think she was a real hero to be getting up on the line so we can start the bike race.
"Racing with three was quite a battle but we enjoyed it and got it, just, thanks to Elinor for putting us up on the line when she wasn’t feeling up for it."
The GB team had earlier qualified second fastest - with Laura Trott rather than Archibald - behind eventual winners Canada. USA took silver.
Both of Britain's men and women's team sprint squads finished outside of the medal positions. The men's line-up of Jason Kenny, Philip Hindes and Lewis Oliva placed fifth, with women's duo Katy Marchant and Victoria Williamson coming ninth.
Germany took gold in the men's team sprint ahead of Poland, with the Netherlands claiming bronze.
Watch: London Six Day highlights - Day Six
China won the women's team sprint, with Australian outfit Jayco-Ais taking silver and Russian squad Rusvelo with bronze.
The racing continues in Cali on Saturday with the women’s sprint, men’s keirin, men’s individual pursuit and women’s scratch race, and the start of the men’s and women’s omniums.
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