As the U16 and U19 National Championships enter the final weeks, there are plenty of players pushing their cases ahead of the finals.The Brumbies were dominant as they came away from Harlequin Rugby Club with wins in both grades over the Melbourne Rebels.Meanwhile, the Western Force took the Queensland Reds to the limit in the U16s before the Reds responded in emphatic fashion during the U19s.High-Performance National Programs Coach Nathan Grey is among several keeping a keen eye on the action as they look to build for the future, highlighted by the Junior Wallabies and the likely return of the World U20 Championships.Rugby.com.au looks at the teams of the week from both competitions as picked by Grey.*Please note the NSW Waratahs had the bye in round four and will not featureUnder 16s ChampionshipsAfter their thrilling contest, the Queensland Reds and Western Force dominate the team of the week, earning five selections each.Force winger Ken Ah Hong was rewarded for his electric double, joined in the backline by scrumhalf Tamarangi Tunui and centre Christoffel Jansen.Manaia Te Tana continues his strong season with his second selection for the year alongside loosehead prop Lee Ruiz.Fullback Chase Oates and Prestyn Laine-Seitu headline the inclusions for the Reds after their strong second-half performances got the visitors back into the contest.Lock Will Pascoe earns his second selection in a row whilst hooker Ewald Kruger and replacement prop Princeton Ioane round out the Queensland contingency.It's an all-Brumby back-row as Alex Hardy is joined by standouts Bailey Bouquiaux and Harry Harrington whilst flyhalf Sam Chapman has been rewarded after his breakout performance.Rebels flyer Andrew Mulipola is the lone selection from the Victorian side as they look to bounce back this week against the Queensland Reds.Team of the WeekLee Ruiz (Western Force)Ewald Kruger (Queensland Reds)Princeton Ioane (Queensland Reds)Will Pascoe (Queensland Reds)Manaia Te Tana (Western Force)Alex Hardy (ACT Brumbies)Bailey Bouquiaux (ACT Brumbies)Harry Harrington (ACT Brumbies)Tamarangi Tunui (Western Force)Sam Chapman (ACT Brumbies)Andrew Mulipola (Melbourne Rebels)Christoffel Jansen (Western Force)Prestyn Laine-Seitu (Queensland Reds)Ken Ah Hong (Western Force)Chase Oates (Queensland Reds)