Born and raised in Gunnedah, the young man grew up playing rugby league through the age groups with his local team, the Bulldogs.

But when the COVID-19 pandemic struck and lockdowns began, Muller stepped away from the sport.

"I've always played for Gunnedah, but I had a couple of years off," he said.

"I just needed a break. I was always going to come back, it was just through that COVID period, that really stuffed things up."

After a couple of years on the sidelines, he found himself sharing a yarn with his good mate, Wil Patterson, at the local watering hole.

It was then that he decided to jump back into the fray.

"I was just at the pub, it was one of those decisions," Muller said.

"Me and [Patterson] just wanted to play again, so we did. We've been talking about it for ages, but we went to the pub and finally did it."

Muller made his return in 2022. That year and the next, he played primarily reserve grade. But in late 2023, he got a taste of first grade.

And now he wants more.

The 21-year-old second-rower got a glimpse of the highest level in Group 4 last year, and his goal is to become a regular contributor to the Bulldogs' top side in 2024.

"I wouldn't mind having more of a run in first grade," Muller said.

"That's the main [goal] really, to spend a bit more time in the top grade. But I've got to put myself in a position where I can get there, so I'll keep working."

A fridgie by trade, Muller is no stranger to gruelling work - and it shows on the field. He is another in the Bulldogs' ceaseless production line of hard-running, tireless forwards who aren't afraid of taking hit-ups from bigger opposition.

With a win on Saturday in their only trial game of this year's preseason, Muller believes there is a newfound positivity among the group after a tough few years near the bottom of the ladder.

And by his own reckoning, there is a different feeling among the playing group this season.

"It's a bit different ... with [coach Sean Hayne] and the young fellas coming back," he said.

"It's pretty good for our first hit-out, that was the first time we've all run together and played together this year, it was good."