The problems are continuing for the Canterbury Bulldogs, with revelations Toby Sexton and Jethro Rinakama may join the casualty ward ahead of this weekend's knockout semi-final against the Penrith Panthers.

The Bulldogs were gallant against the Melbourne Storm but came up short during Friday evening's qualifying final in the Victorian capital and will now face the Penrith Panthers for the right to extend their season.

It won't come without its issues for the Bulldogs though, who are set to lose Stephen Crichton for the remainder of the year to injury.

The centre suffered an ankle injury during the first 20 minutes of the qualifying final against Melbourne and was unable to return, with scans reportedly showing an injury that will keep him out of the finals and Pacific Championships, where he would have been a walk-up starter for Samoa.

Director of football Phil Gould is reportedly suggesting the injury will only be a two to four-week recovery though, suggesting Crichton is a chance of returning for the grand final if Canterbury make it that far.

The Bulldogs' captain was joined on the injury list by key second-rower Viliame Kikau, who may yet be able to play but is feared to have suffered a fractured eye socket, while Enari Tuala was said to have suffered a calf injury that has since been upgraded to a possibly broken leg.

The trio are now joined by Jethro Rinakama, who has had scans on an ankle injury, and Toby Sexton, who has had scans on a sternum injury, per a News Corp report.

Per AAP, the hope is that Sexton will avoid a fracture, while Viliame Kikau is stable with his eye socket so may be a chance to play.

Tuala and Rinakama were already filling in with Marcelo Montoya and Bronson Xerri missing the game against Melbourne, while Sexton replaced Reed Mahoney on the bench but played the best part of an hour after Crichton's injury.

Sexton's form had many suspecting he could be a call up to the starting side for the semi-final against Penrith.

He suffered the injury early in the second half, but managed to play through to fulltime.

If the duo are ruled out, and joined by Tuala, Kikau and Crichton, the Bulldogs will be in dire straits attempting to pick a team to battle the four-time premiers, with Bronson Xerri the only expected return after he missed the Melbourne clash through concussion.

Marcelo Montoya is an outside chance of returning, but if the worst comes to worst, it could mean Canterbury are forced to shuffle their spine around, with Bailey Hayward moving into the halves, Reed Mahoney starting at hooker and Jake Turpin called onto the bench while Matt Burton plays at dummy half.

If the Bulldogs would prefer to keep Burton at five-eighth and Hayward in the spine, then it could be that Jonathan Sua or Blake Taaffe are called into the centres for the clash.

Possible worst-case Bulldogs team for semi-final
1. Connor Tracey
2. Blake Wilson
3. Bronson Xerri
4. Matt Burton
5. Jacob Kiraz
6. Bailey Hayward
7. Lachlan Galvin
8. Max King
9. Reed Mahoney
10. Josh Curran
11. Jacob Preston
12. Harry Hayes
13. Jaeman Salmon
14. Kurt Mann
15. Sitili Tupouniua
16. Samuel Hughes
17. Jake Turpin