Wales captain Scott Quinnell will face the Welsh All Blacks and then miss the next two Celtic League matches, at home to Ebbw Vale and away in Edinburgh, after opting for surgery on his troublesome nose.
The big No 8 has suffered from regular nose-bleeds since he took a knock on his hooter during the British Lions tour of Australia.
He will be out for two weeks, but the Scarlets have Dave Hodges back after his duties for the United States team.
Coach Gareth Jenkins said: "It is a great blow to the side to lose someone of the calibre of Scott, but we have a strong squad to choose from and it is best to get the problem sorted sooner rather than later."
The Welsh Rugby Union has awarded a unique 'President's Cap' to a specific group of players who represented their country between 1945 and 1979, but missed out on international recognition at the time.
Prabhat Mathema, the WRU's National Medical Manager explains the four part Pitchside Suspected Concussion Assessment process the IRB has devised that is being implemented throughout the Dove Men Series and in the LV= Cup this season, which includes the provision for a five minute temporary substitution to allow an assessment to take place.