Not the best man for new roles? (5)

I believe the answer is:

loser

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

'not the best man' is the definition.
I can't tell whether this definition defines the answer.

'new roles?' is the wordplay.
'new' is an anagram indicator.
'roles' with letters rearranged gives 'LOSER'.

'for' acts as a link.

Can you help me to learn more?

(Other definitions for loser that I've seen before include "Opposite of winner" , "Ineffectual person who regularly fails" , "one plays without success" , "Defeated contestant" , "One who frequently fails (colloq.)" .)

I've seen this clue in the Evening Standard.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.