Play opens dourly in a laboured style (11)

I believe the answer is:

ponderously

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'in a laboured style' is the definition.
I can't tell whether this defines the answer.

'play opens dourly' is the wordplay.
'play' is an anagram indicator.
'opens'+'dourly'='opensdourly'
'opensdourly' is an anagram of 'PONDEROUSLY'.

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I've seen this clue in The Independent.

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