Former England captain Pat Sanderson could face another six weeks on the sidelines as he battles to recover from a leg injury.
The Worcester skipper missed the opening two Premiership matches against Northampton and Wasps, and it has now emerged he might not play again until late October.
New Zealander Greg Rawlinson has taken over leadership duties in Sanderson's absence, and is set to continue when unbeaten Leicester visit Sixways on Saturday.
Warriors rugby director Mike Ruddock, meanwhile, has confirmed Marcel Garvey is out for six weeks due to hip trouble, while Garvey's fellow wing Rico Gear is nursing an Achilles problem that means he is an absentee for Tigers' visit.
Josh Strauss has a Scotland call-up in the back of his mind but the Glasgow Warriors back-row admits he must build on an impressive first two seasons in the country to catch Vern Cotter's attention in time for the World Cup.