Graeme Murty has warned Reading it would be difficult to cope without Nicky Shorey and James Harper.
Both players have been linked with moves to the Premier League following the Royals' relegation to the Championship.
Shorey has emerged as a target for Portsmouth in recent weeks and West Ham and Newcastle are also understood to be interested.
Middlesbrough are reportedly ready to pay £3million for Harper but Murty believes it is vital for the pair to stay at the Madejski Stadium.
"I think they would be very, very difficult to replace," Murty told the Reading Evening Post.
"Having said that, nothing in football surprises me anymore so we just have to deal with situations as they turn up."
Murty has been impressed by the way Harper has kept his focus and stayed professional.
He said: "No matter what goes on, when he goes to training he is 100 per cent physically committed and prepared to give his best."