Classic play has to contend with most of these around it (3,6)
I believe the answer is:
the rivals
'classic play' is the definition.
'the rivals' can be an answer for 'play' (I've seen this before). I am not sure about the 'classic' bit.
'contend with most of these around it' is the wordplay.
'contend with' becomes 'rival' (I've seen this in another clue).
'most of' means to remove the last letter.
'around it' indicates putting letters inside.
'these' with its last letter removed is 'thes'.
'rival' going within 'thes' is 'THE RIVALS'.
'has to' acts as a link.
Can you help me to learn more?
(Other definitions for the rivals that I've seen before include "a comedy of manners" , "Play by Sheridan set in Bath" , "keen competitors" .)