Dragons front rower Luke Bailey will miss this weekend's match against Penrith but could miss up to eight weeks with a back injury.
Bailey has a suspected fractured vertebrae and the club is waiting for the results of a bone scan.
Yesterday, Dragons team doctor Martin Raftery cleared Bailey of kidney and lower back damage, however “there was clinical suspicion of damage and further investigation was undertaken today”.
The powerhouse prop was sent for tests yesterday after passing blood after the match on Sunday night.
Dr Raftery said Bailey would miss at least one match and at worst, he could be sidelined for 6-8 weeks.
Ian Donnelly will take his place in the starting line-up at prop. Donnelly last week started in the second row ahead of Brent Kite, but Kite will return to the starting second row spot this week.
Meanwhile, winger Amos Roberts makes a return after serving a one-week suspension, with replacement David Howell going back to Premier League.
Captain Trent Barrett has been named subject to a fitness test on his bruised ankle. If Barrett plays he will become the first St George Illawarra player to play 100 games for the Dragons.
The only other change is John Cross who is expected to start on the bench to play against his former team mates. Cross was rested last weekend with niggly injuries.
TEAM LIST - DRAGONS V PANTHERS - Sunday, May 11
Penrith Football Stadium 3pm NRL
Coach: Nathan Brown
1. Ben HORNBY 2. Amos ROBERTS 3. Mark GASNIER 4. Matt COOPER 5. Hassan SALEH 6. Trent BARRETT (c) 7. Brett FIRMAN 8. Ian DONNELLY 9. Mark RIDDELL 10. Jason RYLES 11. Brent KITE 12. Lance THOMPSON 13. Shaun TIMMINS
14. Chris LEIKVOLL 15. John CROSS 16. Dean YOUNG 17. Damien BOWER