The former Fulham midfielder arrived earlier this summer.
"I always thought they were good players, but until I got here I didn't realise how good they are," Sidwell revealed to The Sentinel.
"I remember talking to the gaffer before I came and he said he was quietly surprised at the standard of the lads when he first came.
"I saw Stoke play a lot last year and thought they were good, but you don't realise how good until you see close up each day."
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