Abu Ogogo and Josh Barrett are doubts to play again for Bristol Rovers this season after being left out of the named squad.
The pair have suffered significant injuries which have forced the Gas to leave them out of their 22-man squad under recently-introduced salary cap rules.
Instead, the Gas named 21 players after Monday's transfer deadline and are mulling their options.
Barrett has suffered a torn hamstring and is ruled out for at least eight weeks, while Ogogo damaged his quad muscle against Rochdale and could miss three months of action. At least one of them will not play again this term.
The Gas will consider adding either man to their playing squad once they prove their fitness, but with doubts they will be fit to play at all before the campaign ends manager Paul Tisdale and director of football Tommy Widdrington are assessing options in the free agent market.
However when asked on Thursday Tisdale told Bristol Live no progress had been made in that regard.
"We’ve ended the window and we had to name the squad, currently there are 21 names there," Tisdale said.
"Abu and Josh both received significant injuries so we’re waiting for full reports before we decide what we’re doing with those two players.
"There’s every chance their injuries will be over a significant amount of time, which would make them unlikely to be a part of the squad.
"We’ve got one more to name in our squad, which’ll be either one of them returning from injuries or looking at the outside market to the other players who are no longer at a club and maybe are able to join us."
Anssi Jaakkola has been left out of the squad, too, with Joe Day and Jordi van Stappershoef named as the goalkeepers, while Liam Armstrong is an under-21 player and does not count against the numbers.
But, when Jaakkola is fit after an Achilles injury – he is due to return to full training in a fortnight – he will replace one of the keepers in the squad with club's given added flexibility in that position.
