But Douglas Vandor of Dewittville, Que., and Morgan Jarvis of Clearwater Bay, Ont., faded after a fast start in the lightweight men's double sculls. They finished fourth, with Greece and Hungary placing one-two to advance to the semifinals.
Michael Braithwaite of Duncan, B.C., and Kevin Kowalyk of Winnipeg finished sixth in their men's doubles scull semifinal and failed to advance to the final.
The two men's crews were the first of Canada's seven boats to fall out of contention at the Games. The Canadian men's and women's eights have already qualified for their finals.
Jennerich and Obee (seven minutes 15.37 seconds) were second to the U.S. (7:13.82) in their repechage. Cuba also moved on to Thursday's semifinal, finishing third.
Jennerich said Sunday the two were "disappointed, but not disheartened" after finishing fifth in their six-boat heat Sunday.
Preparations for the Games were stormy for the lightweight women.
Jennerich, who turned 30 on Monday, shared the boat with both Obee, a 20-year-old from Victoria, and 37-year-old Tracy Cameron of Shubenacadie, N.S., who won the lightweight quadruple sculls at the 2005 world championships and Olympic bronze in 2008 in the pair with Melanie Kok.
In 2010, Jennerich and Cameron teamed up to win the world championship.
Last year they won in Lucerne, a major regatta ahead of the world championships. But Cameron was sidelined with a stress fracture of a rib and Jennerich joined forces with Obee, the team spare, to win silver at the worlds.
Healthy again, Cameron won a row-off with Obee to see who would join Jennerich this year. But Jennerich and Cameron struggled when they got back in the boat, finishing eighth in May at a key pre-Olympic regatta in Lucerne. Cameron retired in early June, saying rowing was no longer fun.
The lightweight men, Vandor and Jarvis, ended up in the repechage after finishing third in their heat.
On Tuesday, they rocketed away from the start and had a 1.7 second lead over Greece after 500 metres. But the Greeks trimmed the deficit to 0.2 seconds by 1,000 metres and then pulled ahead. Hungary and Australia also overhauled the Canadians in the final 500 metres.
In the men's lightweight class, rowers can weigh no more than 160 pounds and the crew average weight can't exceed 154 pounds. For the women, it's 130 and 125.
Niger rower Hamadou Djibo Issaka, meanwhile, continues to win fans as he gets slower at the Games.
The 35-year-old was last in his four-man single sculls lower qualification semifinal Friday, finishing in 9:07.99, off his earlier Games times of 8:25.56 and 8:39.66. His 1,500-metre split of 6:49.37 Tuesday was some 16 seconds off the world best time over 2,000 metres (6:33.35).
Djibo Issaka advances to the F final, earning applause in the process from the crowd.
The 35-year-old Niger champion was given a wild card by the IOC Tripartite Commission, which allows National Olympic Committees to enter up to five athletes for the Summer Games.
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