The Birmingham Mail says the 24-year-old is extremely keen to make the move to The Hawthorns.
Albion had made a season-long loan offer to Manchester City for the winger.
Although a permanent move would appeal more for the Sinclair - who has had six loan spells in the past - he would still be happy to come to Albion for a season, especially if it included an option for a future permanent move.
However, a bigger worry is that City, while they are happy to loan out Sinclair, would be more willing to accept a permanent cash offer should one come in during the coming weeks.
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