Eric Elwood has made three changes to the Ireland side to face Tonga in their final pool game as his charges look to secure the consolation prize of a third seed ranking for the next under-20 World Cup.

Following a heavy defeat to New Zealand and an opening loss to Argentina, Ireland need a win to finish in the top nine.

Martin Dufficy, who replaced outhalf Ian Madigan at half-time in the 65-10 defeat to the All Blacks, returns to the starting line-up, but Ian Porter remains at scrumhalf consigning Dave Moore to the bench for the second game in a row.

Queen University's Chris Cochrane, who also started the 17-9 defeat to Argentina, returns to the left wing instead of Lansdowne's Eamon Sheridan.

David Kearney, whose brother Rob will play fullback against Australia in Melbourne on Saturday, will make his first appearance of the tournament on the right wing in place of UCC's Sean Scanlon.

Openside flanker Paul Ryan captains the side.

In defeat to the All Blacks, Ireland were guilty of a litany of errors, but Elwood maintains his side has not lost its desire and is hoping they can make up for those mistakes in the Cardiff Arms Park on Saturday.

"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," said the former Ireland outhalf.

"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: Niall Morris; David Kearney, Eoin O'Malley, Conor Cleary, Chris Cochrane; Martin Dufficy, Ian Porter; Paul Karayiannis, Jason Harris-Wright, Ben Barclay; Ian Nagle, Eoin Sheriff; Kieran Essex, Paul Ryan (capt), Patrick Mallon

Replacements: Stephen Douglas, Stephen Archer, James Sandford, Michael Entwistle, David Moore, Ian Madigan, Eamon Sheridan