Back row Dan Lydiate has undergone successful surgery to his ankle following the injury sustained in last Friday's game against Edinburgh. He is due to be released from hospital later this week and will return home to recuperate.
The loss of Lydiate has been compounded by the news that fellow back row Hywel Stoddart is expected to miss the rest of the season after suffering a catastrophic knee injury whilst playing for Newport RFC in the Principality Premiership on Saturday.
Elsewhere, lock Rob Sidoli is expected to be unavailable for several more weeks as he recovers from a calf injury.
Dragons squad for Scarlets
Backs
Daniel Evans, Hallam Amos, Tom Prydie, Will Harries, Adam Hughes ,Jack Dixon, Andy Tuilagi, Pat Leach, Ashley Smith, Steffan Jones, Jonathan Evans, Liam Davies,
Forwards
Jevon Groves, Ieuan Jones , Tom Brown, Toby Faletau, Lewis Evans, Nic Cudd, Ian Nimmo, Adam Jones, Dan Way, Nathan Buck, Aaron Coundley, Phil Price, Steve Jones, Hugh Gustafson, Sam Parry.
Players not selected through injury;
Joe Bedford (Shoulder), Tonderai Chavhanga (Knee), Jamie Smith (Ankle), Dan Watchurst (Leg break), Darren Waters (Knee), Rob Sidoli (Calf), Andrew Coombs (Knee), Mike Poole (Knee), Wayne Evans (Back) Dan Lydiate (Ankle) Hywel Stoddart (Knee), Lewis Robling (Cut Knee).
Wales Sevens;
Matthew Pewtner
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