Mike Ruddock has revealed Hal Luscombe and Will Bowley are both doubts for Warriors upcoming final week of the Guinness Premiership season against Gloucester and London Irish due to injury.
Centre Luscombe, who was due to play in Thursday night's friendly against Newport Gwent Dragons, has a slight cartilage tear in his knee.
"Hal was due to play against the Dragons, but unfortunately it looks like he has torn a bit of cartilage and he might need to have surgery on that," revealed Ruddock.
"Nothing major, but it may mean a couple of weeks out. Sometimes it could be key hole surgery, a little bit of a scrape and clear, and within a week the guys back running."
Lock Bowley, who has 20 appearances this season, has a foot injury and will be assessed before the trip to Kingsholm on Tuesday night (7.30pm kick-off).
One player who will miss the derby clash is Kai Horstmann who is set to miss the rest of the domestic campaign with a fractured rib picked up in last weekends European Challenge Cup quarter final win against Brive at Sixways Stadium.
Meanwhile, Tevita Taumoepeau, who has been out since March with a shoulder injury, has under gone successful surgery and is now in the recovery stage while and prop Matt Mullan is due to go under the knife for shoulder surgery on Saturday.
Worcester Valkyries stars Rochelle Clark, Laura Keates and Lydia Thompson have all been named in the 32-player England Women squad for the Old Mutual Wealth Series against France, New Zealand and Canada, along with an away fixture against Ireland in November.