Basicall ywhen the Batsman is set , his Mindset -focus and concentration is only to those regular bowling.However when the change bowler comes in he takes him for granted and looses his focus and tries teh same way but it does not work teh way he anticipates- Thsoe bowlers are called man with GOLDEN ARM- Sachin did that many times- Mudassar Nazar of Pakistan (Opening bat) is also considered that way-
It is all Psychological to conclude
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Once the batsman is set and in form, He wont hesitate to bat any ball from any bowler.Usually when his team has got following good batsmen, He will attend all type of bowling. Indian batsmen are good in attending spin bowling So mostly this change of bowling wont affect Good Indian batsmen.