Collide with tennis tournament (4)

I believe the answer is:

slam

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'collide' is the definition.
(thesaurus)

I cannot understand how the rest of the clue works.

(Other definitions for slam that I've seen before include "Shut loudly and forcibly" , "If it's grand, it wins all 13 tricks in bridge game" , "major contract" , "A grand one is 13 tricks" , "ambitious bid" .)

I've seen this clue in the Sydney Morning Herald.

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