The British Lions wing has not played since returning from New Zealand with a similar problem to the one that has ruled out team-mate Gavin Henson until mid-October. Now he is targeting a similar comeback date as he battles to prove his fitness for Wales's opening game of the Autumn Series, against the All Blacks in Cardiff on November 5.
Ospreys assistant coach Sean Holley said: "It is a worry because Shane just hasn't been able to shake off the problem but it is still our hope that he will be fit for the Heineken Cup and then for Wales in the Autumn."
Williams is the sixth member of Mike Ruddock's squad to be sidelined by a groin problem.
WRU International Skills Coach Jason Strange is a busy man, combining the new role with that of Wales Under 20 attack coach, Ebbw Vale head coach and continuing to teach at Ebbw Fawr Learning Community.
Warren Gatland and Sam Warburton look ahead to this week's crunch RBS 6 Nations tie against France, where the Wales skipper in particular is keen to make his mark, as Paris has proved a bleak place for him in the past.
Following their historic win over England, Wales Under 20 suffered a narrow, 36-34 loss to their Scottish counterparts last weekend, despite outscoring them by five tries to three. Watch the match highlights and reaction.
WRU TV go behind the scenes with the Wales squad as they put the final touches in place ahead of the clash against Scotland at Murrayfield. Follow the squad on their captain's run, the kickers visit to Murrayfield and Neil Jenkins' press conference