Coach Justin Langer admits the absence of Marcus Stoinis is "problematic" for the balance of their side, as Australia continue to sweat on the fitness of their key all-rounder.
Mitch Marsh has flown into London to join the squad as cover, but Australia are waiting to see if Stoinis can overcome the left side strain he suffered while bowling in their defeat to India on Sunday.
In a positive sign, the 29-year-old batted extensively in Taunton's indoor nets on Wednesday, but bowling remains off-limits.
A return for Saturday's match against Sri Lanka at The Oval appears unlikely, but Australia then have a five-day break before their next game against Bangladesh.
