Ireland achieved their highest ever finish in this tournament last year when they finished fifth and Ruddock, now in his third season in charge, believes that win over the hosts was the key to their best JWC.
South Africa recovered to go on and become the first country other than New Zealand to win the competition, and Ruddock believes Ireland can benefit from that win.
“We are in a tough pool but you would like to think after last year that Australia, New Zealand and Fiji would also think they are in a hard pool because Ireland are there.
“We also defeated England and France last year and have gained a lot of respect as a result. It is now up to the current crop to live up to that world class standard.
“And I think they will. They are really looking forward to it. They have worked very hard and the mood in the camp is good. We know it will be tough but that’s always the case in this competition, that’s what makes it so good,” added the former Welsh Grand Slam winning coach.
He has just two survivors from last year, captain and scum-half Luke McGrath and flanker Josh van der Flier.
Two players, winger Adam Byrne and centre Thomas Farrell, have made the starting side even though they were not involved in the Six Nations, while three more who did not play in that tournament, back rowers Jack O’Donoghue and Dan Leavy and prop Edward Byrne, have also made the bench. Edward Byrne’s twin brother Bryan is also on the bench.
Australia, who have former Connacht assistant coach John McKee on their management team, are hoping to bounce back after a disastrous tournament in South Africa where they were twice defeated by France after the wheels came off when they were shocked 15-3 by Argentina having won their opening game 67-12 against Scotland.
The Wallabies have travelled without ten players who are on sevens duty.
IRELAND U-20: R Scannell (Dolphin/Munster); A Byrne (UCD/Leinster), T Farrell (Lansdowne/Leinster), T Daly (Lansdowne/Leinster), R Scholes (Belfast Harlequins /Ulster); S Crosbie (Old Belvedere/Leinster), L McGrath (UCD/Leinster) (capt); P Dooley (Lansdowne/Leinster), G McGuigan (Newcastle Falcons/Exile), A Boland (Lansdowne/Connacht); P Timmins (UCD/Leinster), J Donnan (Ballynahinch/Ulster); C Joyce (Malone/Ulster), J van der Flier (UCD/Leinster), R Murphy (Dolphin/Munster).
Replacements: B Byrne (UCD/Leinster), E Byrne (UCD/Leinster), R Furniss (Worcester Warriors/Exile), S McCarthy (Shannon/Munster), D Leavy (UCD/Leinster), D Shanahan (Clontarf/Leinster), M Roche (Lansdowne/Connacht), D Leader (Galwegians/Connacht)