"He has spent his whole career playing one style of football and now, at the end of his career, he is being asked to play another one altogether," Foster told BBC Radio 5 live.
"He is one of the best goalkeepers the Premier League has seen but that really is not his game."
Foster said managers had to understand the limitations of their goalkeepers and added that Watford boss Javi Gracia had allowed him to play to his strengths.
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"He knows I'm OK with the ball at my feet, but I'm very good at booming it 80 yards up the pitch. He is more than happy with me doing it the way I want to do it," Foster added.
(Reporting by Shrivathsa Sridhar in Bengaluru; Editing by Peter Rutherford)
