10 Dec, 12:23
Ireland's John Lacey will referee his first ever RBS 6 Nations match in February, while Alain Rolland is also included in the Elite Panel in what is his last season.
The other switches are in the second row and back row with Eoin Sheriff and Paul Ryan coming in for James Sandford and Michael Entwistle respectively. Openside flanker Ryan will once again captain the side.
Commenting on Saturday's clash with the Tongans, Ireland coach Eric Elwood said: "The tournament so far has obviously been a disappointment, but we have not lost any of our hunger, this is a must win game for us.
"We need to improve on our accuracy, basic errors have cost us so far and we paid dearly for them. We know we have so much more in us and are looking forward to proving it in what will be another very physical encounter."
IRELAND UNDER-20 TEAM & REPLACEMENTS (v Tonga Under-20s, IRB Junior World Championship, Saturday, June 14, Cardiff Arms Park, kick-off 3pm):
15 - Niall Morris (Blackrock College/Leinster)
14 - David Kearney (Lansdowne/Leinster)
13 - Eoin O'Malley (Old Belvedere/Leinster)
12 - Conor Cleary (Greystones/Leinster)
11 - Chris Cochrane (Queen's University/Ulster)
10 - Martin Dufficy (Dublin University/Leinster)
9 - Ian Porter (Queen's University/Ulster)
1 - Paul Karayiannis (Queen's University/Ulster)
2 - Jason Harris-Wright (Greystones/Leinster)
3 - Ben Barclay (UCD/Leinster)
4 - Ian Nagle (UCC/Munster)
5 - Eoin Sheriff (Lansdowne/Leinster)
6 - Kieran Essex (UL Bohemians/Munster)
7 - Paul Ryan (Blackrock College/Leinster) (capt)
8 - Patrick Mallon (Lansdowne/Leinster)
16 - Stephen Douglas (Ballymena/Ulster)
17 - Stephen Archer (UCC/Munster)
18 - James Sandford (Queen's University/Ulster)
19 - Michael Entwistle (Ballymena/Ulster)
20 - David Moore (Blackrock College/Leinster)
21 - Ian Madigan (Blackrock College/Leinster)
22 - Eamonn Sheridan (Lansdowne/Leinster)
Manager - Phil Orr
Coach - Eric Elwood
Assistant Coach - Dan McFarland
Ireland IRB Junior World Championship Fixtures (Pool A):
Tonga Under-20s v Ireland Under-20s, Saturday, June 14, Cardiff Arms Park, 3pm