Disappointing change in Raleigh Cycling - with brownish-yellow colour trimming handlebars at first (8)

I believe the answer is:

mediocre

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'first' is the definition.
Both the definition and answer are adjectives. Maybe they are linked in a way I don't understand?

I cannot understand how the rest of the clue works.

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(Other definitions for mediocre that I've seen before include "Fairly bad" , "Somewhat inferior" , "Not very good" , "Second-rate, undistinguished" , "Moderate to inferior in quality" .)

I've seen this clue in The Independent.

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