Keeper Cerny missed Saturday's friendly at Stevenage along with Leigertwood, who has an Achilles problem.
"Mikele's is not too much of a problem but discretion is the better part of valour and it's just important it doesn't flare up," said Dowie.
"Radek has a bit of a tight hamstring which is probably going to keep him out for another week. It's nothing major."
Both players are expected to sit out Rangers' pre-season friendly at Northampton on Wednesday night.
BBC