Wales have called up James Botham, Lloyd Williams and the uncapped Willis Halaholo to their injury-hit squad ahead of Saturday's Six Nations clash with Scotland at Murrayfield, the Wales Rugby Union said on Wednesday.
Loose forward Botham, 23 later this month, comes back in after making an impressive start to his international career late last year when he started three matches in the Autumn Nations Cup.
The 31-year-old scrum-half Williams also made three appearances in that competition after being recalled to the squad four years on from winning his last cap, and is chosen ahead of Rhys Webb.
Centre Halaholo, originally from New Zealand and aged 30, joined the Blues in 2016 and was named in the Wales squad at the end of 2019 but had to withdraw through injury.
Flanker Lydiate will miss the rest of the season after suffering a cruciate knee ligament injury in his comeback appearance, scrum-half Tomos Williams has a hamstring tear and centre Johnny Williams also sits out the Scotland match after taking a head knock.