The NRL must consider shortening future seasons and use the growth of the women's game to help address the league's injury crisis, Penrith coach Ivan Cleary says.
The Panthers will welcome Dylan Edwards and Liam Martin back from injury for their visit to Newcastle on Sunday, but have suffered two more outs in their spine.
Five-eighth Jack Cole and hooker Mitch Kenny will miss the match, after suffering minor leg problems that will keep them on ice until after next week's bye.
The rate of high-profile injuries continues to be a concern for clubs.
Kalyn Ponga, Cameron Munster, Nathan Cleary and Tom Trbojevic are among those to miss this year's entire State of Origin series, with soft-tissue injuries the main issue.
According to the NRL's official website, 80 players are currently sidelined through injury.
That equates to about 16 per cent of players in full-time squads being unavailable.
Ivan Cleary is among those to believe the speed of the game is part of the issue, but the Penrith coach also pointed at the league's drawn-out schedule.
As an example, if his son Nathan Cleary remained fit he could plausibly be asked to play up to 34 times this season through a combination of NRL, World Club Challenge, Origin and Test matches.
"At some point we are going to have to look at the length of the season and how much these guys are playing," Ivan Cleary said.
"I'm not sure on all the answers. It definitely needs a look into, which I believe the NRL are open to.
"There has been a lot of chat around (injuries). The amount of high-end players who have gone down has probably exacerbated it.
"We're doing our own research, we haven't been too badly off.
"The game is probably faster and more ball in play than ever. I guess that has to do with it too."
Any potential changes to the schedule would be extremely unlikely before 2028, when the next TV rights deal begins.
The Panthers coach suggested the women's game could help allow for changes to the men's season, with the NRLW and women's Origin pulling in big television ratings.
"The opportunity (is there) with the women's game growing so well," Cleary said.
"There is a chance to maybe work that into the season so the broadcasters are still getting the content they want. Maybe one day."
Cole's injury means Brad Schneider will return to Penrith's halves alongside Jarome Luai against the Knights, while development player Luke Sommerton will play hooker in place of Kenny.
Edwards' return will give him the chance to win back the NSW No.1 jumper after an ankle injury cruelly robbed him of his debut in game one.
Martin will also be looking to prove his fitness for Origin II.
