Containing only celebrities, the whole side initially on pitch (3-4)

I believe the answer is:

all-star

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'containing only celebrities' is the definition.
I can't judge whether this definition defines the answer.

'the whole side initially on pitch' is the wordplay.
'the whole' becomes 'all' (I've seen this before).
'initially' indicates taking the first letters.
'on pitch' becomes 'tar' (synonyms. I am not sure about the 'on' bit.).
The initial letter of 'side' is 's'.
'all'+'s'+'tar'='ALL-STAR'

Can you help me to learn more?

(Other definitions for all-star that I've seen before include "Composed wholly of top performers" , "Comprising only top performers" , "Having a well-known cast" , "Featuring only celebrities" , "Made up of top performers" .)

I've seen this clue in The Telegraph.

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