After a stellar debut season South Sydney flyer Alex Johnston says his Test selection has him going into his second NRL campaign more confident than ever.

The Rabbitohs kick off their title defence away to the Brisbane Broncos on Thursday.

Johnston knows as premiers Souths will have a target on their back this season but says the team is looking forward to it.

“First game, it’s always a challenge to start the season strong,” he said.

“But that’s what we want to do, just play a great game against the Broncos. It will be a great atmosphere and we can’t wait.”

The 20-year-old had a dream debut season scoring 21 tries in 18 games including a four-pointer in the Rabbitohs’ grand final win.

His barnstorming rookie year earned his selection in the Kangaroos’ Four Nations squad and despite not playing Johnston says his confidence is sky high after just being involved.

“Being amongst those amazing players was just a great learning curve and I’ll take that as motivation to try and make more representative sides in the future,” he said.

“I definitely got a lot of confidence out of it. It was something I wasn’t expecting at all.

“Playing one game of first grade was something I wasn’t sure I’d be able to do so to be in that squad was amazing.”

Johnston said he was glad to have the halves pairing of Adam Reynolds and Luke Keary locked in for another couple of seasons.

Reynolds, 24, is committed until the end of the 2017 season, while 23-year-old Keary has re-signed until the end of 2016.

“They’re such good halves so it’s great to have them on board,” he said.