Baseballer in jug? (7)

I believe the answer is:

pitcher

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'jug?' is the definition.
(I've seen this before)

I can't explain the rest of the clue.

(Other definitions for pitcher that I've seen before include "Large jug; thrower" , "One throwing" , "Earthenware jug" , "source of drink?" , "Baseball bowler and large jug" .)

I've seen this clue in the Evening Standard.

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