Influential Albion centre-half Danny Cullip has stunned the table-topping club by demanding a move.
Cullip could now be on his way to free-spending Second Division rivals Cardiff, although the asking price is expected to be around £500,000.
Cullip's shock decision comes after Cardiff enquired about his availability last week.
It also coincides with Albion retaining the Division Two leadership following a staggering 6-1 defeat for Stoke at struggling Wigan last night.
The Argus can reveal that Cullip has been unhappy for some time. He expressed concern about training facilities and Albion's stadium saga long before Peter Taylor succeeded Leicester-bound Micky Adams as manager a month ago.
Taylor said last night: "Danny told me he had spoken to the club before I got here. It's more to do with the training ground and stuff like that which has disappointed him.
"He has 18 months of his contract left and he cannot see that he is going to play in a new stadium. I understand but I am disappointed. It's a bit of a blow."
Knight said: "We haven't had a direct approach from another club, but we have had an approach via a third party.
"Danny is determined to move and his mind is made up as he told me in no uncertain terms. It has come as a surprise to all of us, but this club is big enough to withstand these things."
Knight has told Cullip to put his request in writing, but the club will not stand in his way. "We have got a very exciting season ahead of us and we are not going to keep an unhappy player," Knight added.
"He has grown in stature as a player here, so we will be looking for a big fee."
Cullip was re-united with Adams for the third time when he moved from Brentford for £50,000 just over two years ago following a successful loan spell.
Cullip, who also played under Adams at Fulham and Brentford, is one of the Seagulls' top wage earners and had his contract extended last year until the end of next season.
A firm favourite with the fans, he has been an ever-present in the League under Taylor apart from missing the home game against Colchester through injury.
Cullip's place in the side is unaffected.
He is due to make his 100th Albion appearance in Saturday's FA Cup tie against Shrewsbury at Withdean and Taylor said: "I've got no problem at all about playing him. Danny has assured me he will be absolutely fine."
More Seagulls stuff at thisisthealbion.co.uk
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