Hull FC prop Liam Watts may miss his side's game against Catalan Dragons in Perpignan on Saturday because he cannot find his passport.
The 23-year-old has made nine Super League appearances this season.
"He's been in good form for us, you couldn't make it up," coach Lee Radford said.
"If he can't find it then it is going to hit him hard in the wallet and it would be a massive loss to us because he was excellent for us on Friday."
The player said on Twitter: "Things do get misplaced and I will be doing all I can to hopefully make the trip!! Few days to get it sorted."
With the team set to fly out to France on Friday, the club have had to employ a solicitor to help with obtaining a new passport because of a backlog at the passport office.
In September last year, Wales manager Chris Coleman was forced to fly out to Macedonia after the rest of his squad because he had lost his passport.
In November of the same year, Chelsea and Belgium winger Eden Hazard was dropped by club boss Jose Mourinho after he missed a training session because he had lost his passport in France.