QPR defender Joel Lynch is a major doubt for Saturday's clash with Aston Villa.
The centre-back picked up an injury in last weekend's 5-2 defeat against Nottingham Forest before falling ill this week.
Speaking to the club's official website , Holloway confirmed: “Lynch is a big doubt.
“He picked up a knock on Saturday and he's had a virus in the last few days.
“In fairness to him, he came in on Wednesday and wanted to train. We did some work with him in the gym but he was struggling, so we sent him home."
Elsewhere David Wheeler (ankle), Idrissa Sylla (calf), Jamie Mackie (back) and Grant Hall (knee) all remain sidelined.
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