The Eastlands club have brought in former Rovers chief on a six-month contract with the task of removing marginalised assets.
The appointment of Williams is seen as a shrewd move, he commands great respect respect in the sport and he received a tribute from former Home Secretary Jack Straw when he exited Ewood Park after 13 years in February.
Game over? Wright-Phillips (left), Santa Cruz (centre) and Bellamy (right) all look set for the chop
Stars such as Craig Bellamy, Roque Santa Cruz and Shaun Wright-Phillips are three tipped to be first out of the door as Williams removes problem players and clears funds for further raids in the transfer market.
Santa Cruz is on around ?90,000-a-week and Bellamy is in the last year of his contract and on close to ?4million-a-year, both of whom would have a list of potential suitors, eager to snap them up.
Celtic, Stoke and Everton could be tempted by a move for the Wales international, but Santa Cruz is likely to head to Spain when he finally leaves the North West.
Wright-Phillips has been told he is surplus to requirements and City are expected to slash his fee to facilitate his departure.
In the firing line: Williams (second left) has a number of players to offload
There will be question marks hanging over Wayne Bridge, too. The full-back has returned from his loan spell at West Ham and is another fringe squad player who commands an eye-watering ?90,000-a-week salary and is likely to be touted around.
However, Shay Given and James Milner have been informed they will not be leaving the club this summer. Milner has a number of potential suitors, but will be retained and Given can stay to fight for his place with Joe Hart.
Out in the cold: Given is likely to remain and fight for his place at Eastlands
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Explore more:People: John Williams, James Milner, Craig Bellamy, Shay Given, Roque Santa Cruz, Joe Hart, Jack Straw, Shaun Wright-Phillips, Wayne Bridge Places: Spain, Wales