QPR are preparing for the Premier League promotion playoff against Derby County.
Simpson said: "We have a lot of matchwinners. Everyone has a big part to play and anyone can win it on the day.
"Obviously Charlie with his goal is the main threat for us.
"Everyone has been joking Charlie [Austin] hasn't played in the Premier League. He wants it and I think he has shown that in his performances.
"I'm sure if we get through the final he will prove he's a Premier League striker and score goals."
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