NUIG Connacht Rugby sub-Academy prop Matthew Burke is among the replacements having made his Ireland U20 debut earlier in the campaign. The Ballinrobe native first played with local club Ballinrobe RFC and has represented Connacht at U20 level and is currently lining out for Corinthians at club level.
In the backline, Jordan Larmour will wear the number 15 jersey, having played on the wing for Ireland's opening three games.
Tommy O'Brien moves from centre to the right wing, and Calvin Nash will again captain the side from the opposite flank.
There is a new centre pairing, as Jack Kelly returns from injury to join Ciaran Frawley in midfield.
Scrum-half Jonny Stewart will again partner number 10 Bill Johnston, who kicked 11 points in Ireland's 26-25 World Rugby U-20 Championship pool win over Wales in Manchester last June.
The front-row remains unchanged, with hooker, Tadgh McElroy joined by props Joey Conway and Charlie Connolly.
In the second-row Fineen Wycherley, who made his Munster Senior debut last weekend in the Welsh capital, returns to the side to partner Oisin Dowling, and in the back-row, flanker Gavin Coombes will make his first start of the campaign and is joined in the back-row by Paul Boyle and Number 8 Caelan Doris.
Ahead of the side departing for Wales, Nigel Carolan said: "The management team are very happy with how the side is progressing and developing so far in the Championship, but there is another big test ahead of us this Saturday in Colwyn Bay.
“Wales have been going well in the competition, and despite a loss to England, they had a very big win against Scotland in the last round so they will be coming into this game full of confidence.
“We've had a good two week build-up to this game and had another good day with the senior side last week, so for us it's now about getting out there and putting in a performance.”
Ireland U20 vs Wales U20, Parc Eirias, Colwyn Bay, Saturday 11th March 2017, 6.30pm (Live on RTE 2 from 6.15pm)
15 Jordan Larmour (St. Mary's College / Leinster)
14 Tommy O'Brien (UCD RFC / Leinster)
13 Jack Kelly (Dublin University / Leinster)
12 Ciaran Frawley (UCD RFC / Leinster)
11 Calvin Nash (Young Munster / Munster) Captain
10 Bill Johnston (Garryowen / Munster)
9 Jonny Stewart (Queen's University / Ulster)
1 Joey Conway (UL Bohemians / Munster)
2 Tadgh McElroy (Lansdowne FC / Leinster)
3 Charlie Connolly (Dublin University / Leinster)
4 Fineen Wycherley (Young Munster / Munster)
5 Oisin Dowling (Lansdowne FC / Leinster)
6 Gavin Coombes (Young Munster / Munster)
7 Paul Boyle (Lansdowne FC / Leinster)
8 Caelan Doris (St. Mary's College / Leinster)
16 Ronan Kelleher (UCD / Leinster)
17 Greg McGrath (Lansdowne / Leinster)*
18 Matthew Burke (Corinthians / Connacht)
19 Jack Regan (UCD RFC / Leinster)
20 Marcus Rea (Queen's University / Ulster)
21 Jack Stafford (Shannon / Munster)*
22 Conor Fitzgerald (Shannon RFC / Munster)
23 Colm Hogan (Dublin University / Munster)
*Uncapped at Ireland U20 level
Not considered due to injury
Ireland U20 Six Nations Fixtures/Results
Friday 3rd February 2017
Scotland U20 19-20 Ireland U20, Broadwood Stadium, Glasgow
Friday 10th February 2017
Italy U20 26-27 Ireland U20, Stadio Enrico Chersoni, Prato
Friday 24th February 2017
Ireland U20 27-22 France U20, Donnybrook Stadium, Dublin
Saturday 11th March 2017
Wales U20 v Ireland U20, 6.30pm, Parc Eirias, Colwyn Bay, North Wales
Friday 17th March 2017
Ireland U20 v England U20, 6pm, Donnybrook Stadium, Dublin