Zesh Rehman's Albion future has been thrown into doubt by a mystery illness.
It has sidelined the young midfielder just when he needs to be persuading manager Mark McGhee he is worth keeping on loan from Fulham.
Flu-like symptoms ruled Rehman out of the squad for Saturday's 2-0 home win against Wrexham.
McGhee said: "He's had some tests back at Fulham because he wasn't feeling well.
"They have not showed anything, but he is still not feeling well and he is still not training. His loan is up after the next League game, so we need to review it."
Rehman, 20, was reaching the end of a month on loan with the Seagulls when McGhee was appointed.
The former England youth international, re-signed for another month after returning to Fulham because of an injury crisis, disappointed in his first game under McGhee.
He was substituted at half time in the home defeat by Bristol City and was relegated to the bench for Albion's victory at Notts County.
Richard Carpenter has forged an effective partnership with Mark Yeates, on loan from Spurs, in the centre of the park so McGhee could revise his original intention to retain Rehman for the rest of the season.
Rehman's latest loan expires with the home fixture against Port Vale on December 12.
On Monday McGhee gave the players their first day off training since the Bristol debacle, as a reward for back-to-back wins and because of a busy schedule of five matches in 22 days in December.
Carpenter, who scored Albion's second goal against Wrexham, said: "Training has been hard and good.
"We had to change things because we weren't getting results. We were conceding too many goals, but you don't become a bad side overnight.
"We have worked to put that right and we looked more solid on Saturday."
Ian Holloway's managerial acumen with Queens Park Rangers has been recognised ahead of Albion's visit to Loftus Road in the LDV Vans Trophy on Sunday (1pm).
Holloway has been named Second Division manager of the month for November after guiding Rangers to the top of the table, two places and four points above Albion.
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules hereComments are closed on this article