Phillips advanced from the quarter-finals after finishing as one of the two best-placed riders while Reade was a fifth-fastest qualifier.
"The most important thing is to make it to day two," said Reade.
"It's just survival, it's getting to that final. Any one of the eight riders that make that final have got a chance to step on the top of the podium.
"I'm not bothered whether in the semi-finals I scrape through in eighth place. I know if I do that I've got just as good a chance has anybody to come away with a medal, so that's the plan."
Both athletes were tipped for medal success coming into the Olympics.