Cardiff - Wales coach Warren Gatland says Alun-Wyn Jones and Luke Charteris could miss the 2012 Six Nations because of injury, depriving the World Cup semi-finalists of their first-choice pairing in the second row.
Jones has a toe injury and Charteris is also a long-term concern because of a wrist problem, giving Gatland a selection headache before Wales' first match in the northern hemisphere tournament - away to Ireland on February 5.
Gatland said on Tuesday that Charteris may need an operation that could ruled him out for "four or five months."
The Welsh are likely to rely heavily on locks Bradley Davies and Ian Evans, who will make up the second row for Saturday's Test against Australia at the Millennium Stadium.
Teams:
Wales:
15 Leigh Halfpenny, 14 George North, 13 Scott Williams, 12 Jamie Roberts, 11 Shane Williams, 10 Rhys Priestland, 9 Lloyd Williams, 8 Toby Faletua, 7 Sam Warburton (captain), 6 Dan Lydiate, 5 Ian Evans, 4 Bradley Davies, 3 Scott Andrews, 2 Huw Bennett, 1 Gethin Jenkins
Substitutes: 16 Matthew Rees, 17 Ryan Bevington, 18 Ryan Jones, 19 Justin Tipuric, 20 Tavis Knoyle, 21 Dan Biggar, 22 Alex Cuthbert
Australia:
TBA