Sinclair signed or the Baggies this week.
"Scott has to get his career back on track," said Clarke, "he's a young player who needs to play.
"He obviously has great potential, otherwise a club like Manchester City would not have splashed out they money they did for him.
"He has been at Chelsea as well. So he knows about big clubs. But his best spell playing, creating and scoring was at Swansea.
"We can give him the same at West Brom. He can create and score, so why can't he be part of that World Cup squad?
"There are some places open. In football a week's a long time, never mind six months or a year. For every young winger they want to get to Brazil and represent their country, I think there's a great chance for them all and that includes Scott."
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