Quinn defends Black Cats' ambitions
The Black Cats reached agreement with the Reds over their Academy graduate and gave him permission to discuss personal terms. It is understood striker David Ngog could be used as a make-weight in the deal.
Henderson would become the second high-profile player to leave the Stadium of Light this year after Darren Bent's January departure to Aston Villa, but Quinn has promised that the club is already on the trail of the players manager Steve Bruce believes will take it forward. Quinn said: "We know the areas that need strengthening and the type of player we need in order to progress, and the job of bringing those players to the club is continuing at a pace."
On Henderson he added: "Jordan is a credit to himself, his family and Sunderland's Academy and everyone here wishes him the very best for the future.
"I'm pleased that we got the deal to a level that we felt was right for our club."
Both clubs confirmed that a deal had been agreed on Wednesday after days of speculation over Henderson's future.
Sunderland did not want to sell their home-grown midfielder, who is set to play in the European Championship finals with England's Under-21s.
However, they always knew they might struggle to hold on to a youngster who has already been capped at senior level if a big club came in for him, and were determined to get the full market value in return.
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