The winger, 23, has told the Swans he will not sign a new contract and Curtis says a move to City will happen before the transfer window shuts on 31 August.
"He's not really interested in signing a new contract and I think Man City have made a bid," Curtis said.
"It's just a matter of time before it happens and it's good for both parties."
Sinclair scored eight goals in the Premier League last season and 19 the season before as Swansea won promotion from the Championship via the play-offs.
The former Chelsea trainee, whose current deal runs out at the end of the season, came on as a substitute in Swansea's 5-0 win at QPR on Saturday, scoring the fifth goal.
"He's been terrific for us, to be fair. We've had two seasons out of him and he was superb in the Championship and virtually his goals got us promotion," Curtis added.
"Last year as well he wasn't maybe quite as effective as he was his first year - obviously it was a lot tougher opposition - but he's been absolutely magnificent.
"Like Joe [Allen, who joined Liverpool] we wish him all the best, but as long as the club keeps pushing forward that's the main thing.
"It obviously gives Scott the chance to settle in at his new club and it gives us the opportunity to buy a replacement for Scott."
One new recruit poised to arrive at the Liberty Stadium is South Korea midfielder Ki Sung-Yueng, after Celtic accepted a bid of around £6m for the 23-year-old.
Celtic manager Neil Lennon described the deal as "good business".
http://www.bbc.co.uk/sport/0/football/19327135 | 
發表於 21-8-2012 19:08:55
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