Sinclair played for both City and West Ham, and he wants both of them to have a successful campaign.
Both City and West Ham are in the running for a top-four finish in the Premier League, and so are Manchester United.
Leicester City, Tottenham Hotspur and Arsenal appear to be set to claim the top three places, which means that the fourth and final Champions League spot is up for grabs.
City have arguably the best squad in England, and Manuel Pellegrini’s side will be favourites to finish above United and West Ham in fourth place.
The Hammers will take on Everton in the semi-finals of the FA Cup if they get the better of Manchester United at home in the quarter-final replay.