Wales face an anxious wait to discover the extent of star second-row forward Ian Evans' latest injury worry as the World Cup approaches.

Evans has been ruled out of Saturday's vital tournament build-up clash with Argentina at Millennium Stadium with a damaged collarbone having not played since hurting his left shoulder on December 27th against Cardiff.

His place has been taken by Ospreys team-mate Alun-Wyn Jones, whose last outing was in the number six jersey as England blew Wales away in the nine-try 62-5 rampage at Twickenham on August 4th.

Jones' place on the replacements' bench has yet to be announced, but it should be a straight choice between the versatile back-five player Michael Owen or Gloucester's Will James.

An operation and lengthy rehabilitation brought Evans back into contention for the World Cup, but he suffered an injury to his left collarbone in training this morning.

The best-case scenario would leave Evans free to face France on Sunday, August 26th, but would leave him desperately short of match practice going into the tournament.

Coach Gareth Jenkins has made no secret of pinning huge hopes on the Ospreys 22-year-old's ability to help provide a dramatic and much-needed improvement to a lineout phase that has struggled to meet the demands of Test rugby under his reign.