Whether it be footy, cricket or even boxing, the brothers sent their parents crazy with their constant need to compete while growing up in Bathurst.

Remarkably, they never found themselves on the same team throughout promising junior careers.

That all changed on Saturday night when Lachlan joined his older brother on the field In the second half of the ACT Brumbies' trial win over the Fijian Drua at Viking Park.

The pair relished the opportunity and Lachlan's goal now is to ensure it's not the last time he teams up with his brother this season.

"It's one thing to be able to play your first game for the Brumbies but it's a lot better when you get to do it with your family and especially big brother looking over your shoulder," Lachlan said.

"My first focus is trying to get that Super Rugby debut with him but you never know what's going to happen. As much as rugby is a game of skill, it's a game of luck and you've got to wait for your opportunity and step in when it comes. Hopefully I'll be ready and hopefully we'll be able to do it together."

It's hard to believe many consider Lachlan to be an even hotter prospect than his older brother when you consider what Tom achieved last year.

The versatile forward overcame a rare foot injury to return midway through the Super Rugby season before earning a Wallabies debut. Hooper was one of the few bright spots amid a disastrous World Cup.

Lachlan achieved representative honours of his own last year and was selected for the Junior Wallabies before leading the ACT under 19s to a historic national title.

Tom is his brother's biggest cheerleader, but recognises he faces a battle to stay one step ahead of him. It's a challenge he's embracing as he prepares for a challenging Brumbies campaign.

"He competes against me at training and the boys put us up against each other," Tom said. "When I remember he's three years younger, it gives me an extra rev up so I've gotta keep on it."