Stares at a playing error by Les (5)
I believe the answer is:
ogles
'stares at' is the definition.
(I've seen this in another clue)
'a playing error by les' is the wordplay.
'a playing error by' becomes 'og' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'og'+'les'='OGLES'
Can you help me to learn more?
(Other definitions for ogles that I've seen before include "Looks at (someone) lecherously" , "Looks longingly at" , "Leers" , "Casts amorous glances" , "Looks at amorously, makes eyes at" .)