As multiple teams prepare for Round 13, several State of Origin representatives are racing the clock to be fit and available ahead of this weekend's matches.

Although Gold Coast Titans skipper Tino Fa'asuamaleaui was initially in doubt for this week's match, coach Des Hasler confirmed that "he is ok" and will play against the Melbourne Storm at his weekly press-conference viaย AAP.

However, South Sydney Rabbitohs star Latrell Mitchell is racing the clock to be available for Sunday's match against the New Zealand Warriors and a decision will be made on him tomorrow, according toย News Corp.

It is understood that all Penrith Panthers players will back-up for this weekend's match and so will Valentine Holmes for the Dragons.

While Holmes will back-up for the St George Illawarra Dragons, coach Shane Flanagan confirmed on Thursday that former Australian rugby sevens star Nathan Lawson will play his first match of NRL tomorrow, replacing Christian Tuipulotu on the wing.

โ€œCT is very close. We could have pushed him if it was a semi-final or something like that,โ€ Flanagan said on Thursday.

"With his history, we told him he was playing all week and we'd get him to the start line, and then we were always going to pull him at the last minute because he's had that hamstring that has caused a few problems.

โ€œOur staff thought it would be better off if he had a really good training week and then get him ready for next week.โ€

Parramatta Eels halfback Mitchell Moses is also in doubt with calf tightness.