Be abundant due to a team change? (4)

I believe the answer is:

teem

I'm a little stuck... Click here to teach me more about this clue!

'be abundant' is the definition.
(I've seen this in another clue)

I don't understand the remainder of the clue.

(Other definitions for teem that I've seen before include "stream" , "Swarm around meet" , "Rain buckets" , "Be prolific" , "Pullulate" .)

I've seen this clue in the Evening Standard.

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