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.
GB7s women left their England base to train in Wales this week. Olympic Games hopeful Rachael Burford gives WRU TV's Graeme Gillespie her thoughts on Welsh teammate Jasmine Joyce - a 'one touch wonder'
The GB7s women's squad is currently training at Wales' Centre of Excellence where assistant coach Richie Pugh tells WRU TV's Graeme Gillespie some 'tough calls' will have to be made when it comes to finalising the 12 spots for Rio's Olympic Games.
Wales U20's Billy McBryde is looking forward to starting his first game against New Zealand this afternoon in the World Rugby U20 Championship where his side are looking to gain revenge from last week's pool defeat to the Kiwis.