CARDIFF, United Kingdom - Wales prop Samson Lee has been ruled out of Sunday's Six Nations clash against Scotland at Murrayfield.
Lee suffered a knock to his head during last weekend's 21-16 Millennium Stadium defeat against England.
"Lee was unable to complete the final component of the return to play protocol and has been ruled out of the second RSB 6 Nations fixture," the Welsh Rugby Union confirmed on Friday.
Lee's absence comes after it was decided this week to rest wing George North for the Edinburgh trip after he suffered two heavy blows to his head during the England game.
North had been replaced by Scarlets back Liam Williams, and Wales head coach Warren Gatland has now made a second switch as his players look to bounce back following the England loss.
Lee's place has been taken by Ospreys tighthead Aaron Jarvis, with Cardiff Blues forward Scott Andrews named on the bench.
Team (15-1) Leigh Halfpenny; Alex Cuthbert, Jonathan Davies, Jamie Roberts, Liam Williams; Dan Biggar, Rhys Webb; Taulupe Faletau, Sam Warburton (capt), Dan Lydiate; Alun Wyn Jones, Jake Ball; Aaron Jarvis, Richard Hibbard, Gethin Jenkins Replacements: Scott Baldwin, Paul James, Scott Andrews, Luke Charteris, Justin Tipuric, Mike Phillips, Rhys Priestland, Scott Williams