France: The defending world champions won the tournament on home soil last summer and there are a number of familiar faces including world player of the year Jordan Joseph and the lavishly gifted Louis Carbonel who kicked 23 points in last year's final. France lost to Ireland and England in the Six Nations but will be strong contenders to win the pool and make the semi-finals.
Wales: Leicester Tigers' backrow Tommy Reffell return to fitness is a huge boost and offsets the loss of Taine Basham, while in Ryan Conbeer, Tomi Lewis and Rio Dyer, Wales have three players who togged out for their country on the World Sevens circuit this season. They won two of five matches in the Six Nations but the squad of definitely stronger now.
Argentina: Juan Pablo Castro and Gonzalo García will play their third U20 Championship, while it will be the second for Santiago Chocobares, Mateo Carreras, Gonzalo García, Joaquín de la Vega, Bautista Pedemonte and Ignacio Mendy. Coach Jose Pellicena took his side to South Africa last month where they beat the hosts and Georgia in warm-up matches.
Fiji: They took part in the four-cornered Oceania Under-20 Championship and after losing to New Zealand and Australia, matches in which they were competitive, the beat Japan in their final outing. Promoted as winner's of last year's World Junior Trophy tournament, there are five survivors but the squad has been together for almost nine weeks.
Ireland: Ireland head coach Noel McNamara lost 18 players to injury before and during this tournament last season and the issue is once again a conversation point as the 2019 Under-20 Six Nations champions prepare to head for Argentina. Captain and centre David Hawkshaw, wing Conor Phillips, outhalf Harry Byrne and flanker Scott Penny have been joined on the list of absentees by flanker Martin Moloney (knee) and Clontarf secondrow Brian Deeny who tore ankle ligaments in training. Sale Sharks backrow Ciaran Booth, who played for the Ireland Under-19 team earlier in the season, has been included in the squad as has another Irish-qualified player now based in Ulster, in Iwan Hughes.
England: Coach Steve Bates has retained seven players from the group that were beaten in last year's Junior World Championship by France including Ted Hill who made his full England debut against Japan in the November internationals but Harlequins outhalf Marcus Smith is out having been called into an England XV squad to face the Barbarians. Joe Heyes, Joel Kpoku, Josh Basham, Aaron Hinkley and centre Fraser Dingwall provide both Premiership and tournament experience. Prop Marcus Street has been replaced by fellow Exeter Chief James Kenny while hooker Samson Ma'asi misses out on medical grounds. England finished third in the Six Nations but as anyone who witnessed the opening 20 minutes against Ireland in Cork will recall, there is no shortage of power and pace.
Australia: The Junior Wallabies won the recent Oceania Under-20 Championship beating New Zealand 24-0 in the final and head coach Jason Gilmore has nine players Esei Ha'angana, Will Harrison, Trevor Hosea, Isaac Lucas, Fraser McReight, Josh Nasser, Pat Tafa, Semisi Tupou and Michael Wood who played in the Junior World Championship in France last year. Dundalk-born scrumhalf Michael McDonald is part of a squad that includes Australian Sevens speedster Triston Reilly and Nick Frost who recently signed from the Brumbies from the Crusaders academy. While New Zealand were short of several players in that final defeat, the Aussies fully deserved their triumph that was predicated on excellent defence and in taking their chances.
Italy: Coach Fabio Roselli has selected six players who played in the tournament last year when Italy finished eighth, prop Matteo Nocera, Niccolo Tadia, backrow forwards Antoine Koffi and captain, Davide Ruggeri and centres Damiano Mazza and Matteo Moscardi. There are four 18-year-olds in the squad included the highly rated prop Matteo Drudi. Stephen Aboud has overseen the development of the Italian underage structures since Conor O'Shea persuaded the Dubliner to take overversee the programme and their progression has been tangible in results and in developing players. Italy won one match in the Six Nations, beating Scotland but were only beaten 35-31 by world champions, France.
Scotland: Props Euan McLaren and Murphy Walker, secondrow Ewan Johnson, flanker Marshall Sykes and outhalf Ross Thompson return from last year's tournament in France. Carl Hogg's squad face a ridiculously tough pool and that includes a Georgian team that beat them in the ninth place playoff last season. They won one match in the Six Nations against Wales and will warm-up for the tournament by playing against a club side in America.
South Africa: The Junior Springboks have one of the least experienced squads in terms of Junior World Championship experience but they include the outstanding Phendulani Buthelezi – he is captain this year – centre Rikus Pretorius, outhalf David Coetzer and prop Asenathi Ntlabakanye, who won a bronze medal in France last year. They prepared for the tournament by travelling to Britain for games against England and Wales.
New Zealand: Craig Philpott has been able to name a squad that includes seven players from last year's tournament, 11 with Mitre 10 Cup experience and in Leicester Faingaanuku, Etene Nanai Seturo and Billy Proctor a triumvirate with Super Rugby Championship experience. Their defeat to the Aussies is the first time they have lost in the U-20 Oceania Championship but expect a bounce back in Argentina.
Georgia: The Georgians beat both Ireland and Scotland during last year's tournament in France and also have victories over Argentina and Italy at this level in previous seasons. They'll certainly fancy the prospect of taking on the Scots in the final round of pool fixtures.
Ireland's Under-20 Junior World Championship fixtures (live on Eir Sport)
Tuesday, June 4th
Pool A: England v Ireland, Club de Rugby Atheneo Immaculada, Santa Fe (7.30pm, Irish time)
Saturday, June 8th
Australia v Ireland, Club de Rugby Atheneo Immaculada, Santa Fe (2.30pm, Irish time)
Wednesday, June 12th
Italy v Ireland, Club de Rugby Atheneo Immaculada, Santa Fe (2.30pm, Irish time)
Monday, June 17th
Semi-Finals/Play-Offs: Racecourse Stadium, Rosario or Club Old Resian, Rosario
Saturday, June 22nd
Finals Day: Racecourse Stadium, Rosario or Club Old Resian, Rosario.