Large roses ordered for beaten contestants (6)
I believe the answer is:
'beaten contestants' is the definition.
'losers' can be an answer for 'contestants' (loser is a kind of contestant). I am unsure of the 'beaten' bit.
'large roses ordered' is the wordplay.
'large' becomes 'l' (eg in clothes sizes).
'ordered' is an anagram indicator.
'roses' is an anagram of 'osers'.
'for' is the link.
Can you help me to learn more?
(Other definitions for losers that I've seen before include "Odd sorels never win" , "Also-rans" , "Odd sorels don't win" , "They're unsuccessful" , "They're defeated" .)