Cardiff Blues U16 North and South have named their match-day squads for Wednesday's derby clash at Y Wern, Merthyr (KO 7.15pm).
Both sides go into Wednesday's clash in scintillating form, having won three consecutive games in the WRU Regional Age Grade championship.
Cardiff Blues North have made four changes to their side that beat Ospreys East at Llandarcy on February 19.
Rhys Lewis and Jack Little are replaced in the pack by Iestyn Haskins and Callum Hanley. In the backline, Dafydd Thomas and Ieuan Chedzoy come into the starting XV, taking the place of Jacob Beetham and Ieuan Alder.
Hooker Aneurin James continues to captain the side.
Meanwhile, Cardiff Blues South, who defeated Dragons South in their last outing, have also made four changes to their starting line-up. Emyr Jones remains as captain, and is partnered in the second row by Teddy Williams, who replaces Kurtis Hackman.
In the back-row, Finli Barber is replaced by Craig Miller at openside, and is joined by Aron Churchill and Reuben Williams, who keep their places from the 36-7 win over Dragons South at BT Sport Cardiff Arms Park.
A shake-up in the backline sees a change at outside-half, with Ioan Lloyd replacing Evans Thomas, while Max Lane is named on the wing in place of Casey Davies.
Cardiff Blues North U16 v Cardiff Blues South U16
The Wern, Merthyr - Wednesday 1 March, 7.15pm KO
Cardiff Blues North U16: Ieuan Chedzoy; Iwan Price-Thomas, Dafydd Thomas, Ioan Evans, Will Clapham; Jorge Lucey, Kieran Gough; Mathew Iles, Aneurin James (capt), Iestyn Haskins, Mitchell Barnard, Morgan Davies, Callum Hanley, Lloyd Gregory, Ieuan Pring
Replacements: Mitchell Savage, Garyn Phillips, Rhys Lewis, Niall Jackson, Jack Little, Bailey Roberts, Sam Coleman, Lloyd Wilkins
Cardiff Blues South U16: Macauley Coombes; Tomi Owens, Louis Rees-Zammit, Cain Sutton, Max Lane; Ioan Lloyd, Lloyd Smith; Jake O'Shea, Joel Coughlin, Luc Williamson, Teddy Williams, Emyr Jones (capt), Rueben Williams, Craig Miller, Aron Churchill
Replacements: Harry Fry, Tyler Ferraera, KC Kelly, Kurtis Hackman, Cavell Sinclair, Ioan Williams, Evan Thomas, Pat Thomas