The 23-year-old has struggled with injuries in his time at Man City and is being allowed to depart the club with the Premier League champions set to sign Frank Lampard on loan.
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The Black Cats are expected to tie up the move in a package worth more than 10 million pounds, taking the 23-year-old to the Stadium of Light on a five-year deal.
Sunderland boss Gus Poyet had previously spoken of his hope to push a couple of transfers through in the coming days, saying: "You'll know in two or three days. I'm expecting good things this week.
"I'm really looking forward to seeing the final touches with the players we bring in to make sure we have a competitive squad.
"It's quality sometimes, the different ability that you need in the last third, more players, everything really. But it is clear that we need to score more."
The central midfielder has been capped three times by England but is deemed surplus to requirements at the Etihad Stadium, particularly given Frank Lampard's impending loan move.
Rodwell is set to reject a host of other Premier League clubs for a move to the northeast.