Spanish wine jar I smashed when empty (5)

I believe the answer is:

rioja

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'spanish wine' is the definition.
(I've seen this before)

I cannot understand how the rest of the clue works.

(Other definitions for rioja that I've seen before include "Dry red wine from Spain" , "Popular Spanish wine" , "Spanish wine type" , "Open space (ancient Greek)" , "it comes from grapevine" .)

I've seen this clue in The Globe and Mail.

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