| MD | Players | Nationality | DOB | A(D) |
|---|---|---|---|---|
| 05-May-2018 | Steffan Evans | Wales | 01-Sep-1994 | 23(246) |
| 05-May-2018 | Rhys Patchell | Wales | 17-May-1993 | 24(353) |
| 05-May-2018 | Samson Lee | Wales | 30-Nov-1992 | 25(156) |
| 05-May-2018 | Tadhg Beirne | Ireland | 01-Aug-1992 | 25(277) |
| 05-May-2018 | Rob Evans | Wales | 14-Apr-1992 | 26(21) |
| 05-May-2018 | Steven Cummins | Australia | 29-Mar-1992 | 26(37) |
| 05-May-2018 | Tom Prydie | Wales | 23-Feb-1992 | 26(72) |
| 05-May-2018 | James Davies | Wales | 25-Oct-1990 | 27(192) |
| 05-May-2018 | Scott Williams | Wales | 10-Oct-1990 | 27(207) |
| 18-May-2018 | Johnny McNicholl | Wales | 24-Sep-1990 | 27(236) |
| 05-May-2018 | Gareth Davies | Wales | 18-Aug-1990 | 27(260) |
| 05-May-2018 | Lewis Rawlins | Wales | 13-Apr-1990 | 28(22) |
| 05-May-2018 | Leigh Halfpenny | Wales | 22-Dec-1988 | 29(134) |
| 05-May-2018 | Hadleigh Parkes | Wales | 05-Oct-1987 | 30(213) |
| 18-May-2018 | Aaron Shingler | Wales | 07-Aug-1987 | 30(285) |
| 05-May-2018 | Ken Owens | Wales | 03-Jan-1987 | 31(123) |
| 05-May-2018 | John Barclay | Scotland | 24-Sep-1986 | 31(223) |
MD = Match date,
DOB = Date of birth,
A(D) = Age(days).