Steve Bruce has admitted everyone associated with Sunderland is 'massively let down' by Darren Bent's decision to leave for Aston Villa.
The two clubs have completed a deal for the England striker thought to be in the region of £18million.
Bent shocked the Sunderland board when he handed in a written transfer request in the aftermath of the 1-1 draw with Newcastle on Sunday.
Bruce, though, is determined to shake off the loss of his star striker as he continues to build a young and entertaining team.
"It's hugely disappointing that Darren has decided that his future lies away from Sunderland and the players, our supporters and the club as a whole have every right to feel massively let down," he told the club's official website.
"The timing is especially hard to take, given that we are progressing positively and are in a great position to push on.
"Everyone has been nothing but supportive of Darren in has time at Sunderland but it's obvious he's not been himself in training.
"We've certainly not seen the best of him in games in recent weeks - and we now understand why.
"I've always stated that my aim is to build a talented, young squad for the long-term to help the club achieve sustained success.
"I want Sunderland fans to know that our ambitions haven't changed on that front."
Chairman Niall Quinn was stung into action and feels he has got his club the best deal possible.
"Darren has now left the club and it's important we move on quickly," he added.
"We've worked hard in the last 36 hours to get what we feel is a fair price for him."
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