The ever-present Ospreys trio of captain, Dewi Lake, Tiaan Thomas-Wheeler and Cai Evans will line-up for Wales U20 against New Zealand on Monday.
The sides meet in the 5th place semi-final of the World Rugby Championship in Rosario (KO 2.30pm BST).
There are four changes in the pack and two in the backline.
The changes behind the scrum mean there are also two positional switches with Deon Smith moving from the left wing to right wing to allow Scarlets’ Ryan Conbeer his usual post wearing 11 while Max Llewellyn’s inclusion at outside centre sees Tiaan Thomas-Wheeler move to inside centre with Sam Costelow dropping down to the bench.
Up front captain Dewi Lake will have two new props alongside him with Kemsley Mathias getting the nod at loosehead while Ben Warren starts on the tighthead with Tom Devine and Nick English both moving to the bench.
In the second row Morgan Jones, who made his presence felt when coming on as a replacement against Fiji, joins fellow Scarlet Jac Price in the second row with Ed Scragg dropping down to the bench.
There is a welcome return for Dragons flanker Lennon Greggains who hasn’t played since the opening game of the campaign against Argentina through injury. His presence allows Iestyn Rees a well-deserved break but the Scarlets back row is certain to figure from the substitutes bench later in the match.
"We've always emphasised how important the squad of 28 is, and this is getting more and more evident the longer we go in to this competition," said Williams.
"Playing New Zealand is a great test for us, and a great fixture to be preparing for. They are rightly regarded as one of the best teams in the world at this age group.
"We don’t always get the opportunity to play southern hemisphere teams so this is a big challenge for us but one we have prepared well for."
U20 World Rugby Championship
Wales U20 v New Zealand U20
Racecourse Stadium, Rosario, 17 June, KO 2.30pm UK (Live on S4C)
15 Ioan Davies (Cardiff Blues)
14 Deon Smith (Dragons)
13 Max Llewellyn (Cardiff Blues)
12 Tiaan Thomas-Wheeler (Ospreys)
11 Ryan Conbeer (Scarlets)
10 Cai Evans (Ospreys)
9 Dafydd Buckland (Dragons);
1 Kemsley Mathias (Scarlets)
2 Dewi Lake (Capt – Ospreys)
3 Ben Warren (Cardiff Blues)
4 Morgan Jones (Scarlets)
5 Jac Price (Scarlets)
6 Lennon Greggains (Dragons)
7 Tommy Reffell (Leicester Tigers)
8 Jac Morgan (Aberavon/Scarlets)
Reserves: Garin Lloyd (Ospreys), Rhys Davies (Ospreys), Nick English (Bristol Bears), Ed Scragg (Dragons), Iestyn Rees (Scarlets), Harri Morgan (Ospreys), Rio Dyer (Dragons), Sam Costelow (Leicester Tigers), Teddy Williams (Cardiff Blues), Tom Devine (Dragons),
Ioan R Davies (Cardiff Blues), Will Griffiths (Dragons), Tomi Lewis (Scarlets)