Dylan Walker has put his hand up to continue playing fullback in Greg Inglis' absence despite a trying debut at the back.

Walker was a late swap for Alex Johnston at fullback in the Rabbitohs' 47-12 loss to Brisbane on Thursday night with Johnston staying on the wing. Despite Johnston, who has been being touted as the club's long-term fullback option post-Inglis, playing at No.1 when the Rabbitohs skipper has been missing, Walker filled in at the back with mixed results. He launched himself into his work by charging into the Broncos defensive line from kick returns early in the game but the defensive workload of his own side saw his energy zapped.

"I enjoyed it," Walker said. "The lungs were breathing heavily but that was part of it. I want to keep learning. [Coach Michael Maguire] wanted me out the back to get a bit of energy.

"I was knackered in that one bit when [Andrew] McCullough almost scored. Kodi Nikorima fooled most of us and that's how [Anthony] Milford scored [one of his tries]. I've got to keep working on it."

Inglis is not expected to miss the Rabbitohs final regular game of the season against the Roosters as he recovers from minor knee surgery. While Walker said he battled with the extra physical demand of switching from centre to fullback, he wants to continue to play there with Inglis sidelined.

"I would like to [keep playing there] to keep building on my game," Walker said. "It's up to Madge [Maguire] if he wants to keep me there. I want to learn the position. It's an exciting role."

While most new fullbacks are tested under the high ball, it was a rampaging Broncos side which Walker had to contend with. None more so than Corey Oates who tussled with Walker for 30 metres as the Broncos winger fended his opposition player away before scoring.

"I thought I had him and then he get that big right duke out and he was holding me the whole way," Walker said. "It was something I should have taken care of. There were a lot of line breaks and a couple of tackles I should've made. They got me in the end. It was a tough old one at the back. It was an attitude thing."