Albion have lost their battle to keep hold of Albion loan star Steve Sidwell.
The Arsenal midfielder completes a £75,000 move to Reading today, subject to a medical.
The Seagulls matched Reading's bid for the prolific 20-year-old, but boss Steve Coppell's fears were confirmed by two telephone conversations with Sidwell yesterday.
He told Coppell in the morning he was "90% certain" to sign for Reading. Sidwell has now said yes to Reading's offer following last-ditch talks with Arsenal manager Arsene Wenger.
Coppell revealed: "He is going to Reading for a medical. I am not surprised, it is an opportunity which was very hard for him to turn down.
"I know he went back and had a word with Arsene Wenger. He intimated he would like Steve to stay, but couldn't promise anything for him.
"There is so much competition for midfield places at Arsenal and he just wants to be playing."
Coppell is now hoping the money made available by chairman Dick Knight in an effort to keep Sidwell at the club will enable him to sign a replacement, but he won't be rushed.
"I know there are funds available, but I know how valuable money is at Brighton and I don't want to waste it," Coppell said.
"The players at the moment are working their socks off."
Albion are also likely to be without their other loan signing from Arsenal, Graham Barrett, for Saturday's home game against Portsmouth.
Barrett headed north last night for talks with Preston boss Craig Brown over his proposed move to Deepdale, so the Republic of Ireland striker is not training with the Seagulls today.
Coppell is still hoping to sign a goalkeeper before the Portsmouth match after Michel Kuipers sustained a recurrence of right thigh trouble in Tuesday's FA Cup exit at Norwich.
He said: "The early prognosis is that Michel will probably be out for a minimum of four weeks. I've put loads of phone calls in but not had much of a return so far.
"I have got a couple of options and I am just seeing what is available before I commit.
"I've got no problem going with Will Packham if needs be, but we have only got the one goalkeeper."
Albion have suffered another injury setback involving midfielder Simon Rodger. A scan on the secondary damage to Rodger's broken big toe in the League win at Norwich on Boxing Day has revealed a further small fracture nearby, ruling the midfielder out until February.
The injury was accidentally caused by Albion captain Danny Cullip.
Rodger said: "I went up with Danny and one of their players at a corner and it was Danny who actually caught me.
"It bent my toe right back and I need another couple of weeks to let the fracture heal up.
"It is very frustrating. I have never had any problems with my feet at all and I just want to be out there."
The only consolation for Albion and Rodger is the two-week break they have after Portsmouth before their following match at fellow strugglers Walsall.
More from the camp at thisisthealbion.co.uk
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