The men's eight, who finished fourth in their heat behind Britain, the Netherlands and Russia, where only the first two advanced straight to the final, must get inside the top five to qualify for next year.
The women's quad, also fourth in their heat, need to make the final, then finish in the top five.
The good news story out of yesterday's racing was the effort of the women's eight, who finished second behind Canada, clocking 6min 05.650s to move into their final. They, too, are chasing a top-five finish at the regatta to take the direct route to Rio.
The United States, the Netherlands and Britain recorded faster times than New Zealand in the other heat, but they now have four full days to prepare for the final.
Four crews have moved straight into semifinals. Lightweight single sculler Zoe McBride, the men's quad of John Storey, George Bridgewater, Jade Uru and Karl Manson, and women's pair Kerri Gowler and Grace Prendergast have semis tomorrow night (NZT) while Macfarlane and Stevenson race 24 hours later.