After years of using his size to overcome rivals, the 19-year-old tight-head prop realised that bulk alone was not going to work when he took the giant step up from colts to first grade.

In some positions on the field, the rise can be seamless.

But in the front row, where technique and experience are at least as important as size, sometimes even more so, the transition can be massive.

"It has been pretty challenging," Christensen said. 'The first weeks were taxing on the body and mentally it was also draining.

"Every week I am getting more comfortable and my role in the team is becoming more defined. I am now starting to be able to play my own game."

Until this season, Christensen's game was pretty match bash and barge.

Standing 183 centimetres and tipping the scales at 110 kilograms, he could do what he wanted throughout out juniors and last season in colts.

"I have always been big for my age and pretty much just used my size," he said.

"It wasn't that challenging. I didn't have to prepare myself as much, but stepping up you have to prepare better and take it that bit more serious."

After making his first-grade debut towards the end of last season, Christensen was keen for more despite still being eligible for colts (under 20s).

"I was keen to have a good crack," he said. "But I didn't think I would get 80 minutes as often as I have. It has been good."

Christensen got a taste of what to expect when he played tight-head for NSW Country under 20s against ACT Brumbies Academy and NSW Waratahs Academy teams early in the season.

"The academy games were very full-on," he said. "It made me realise, playing at that level, how serious it can be even at my age.

"It was good to play them and see how we aimed up."

With former Country prop Tony Sambell back after a season out with a torn pectoral muscle and premiership-winning prop Nick Crosskill on deck, coach Dan Beckett could have taken his time with Christensen.