Improve on last place in sprint (that hurt) (7)
I believe the answer is:
retouch
'improve' is the definition.
(I know that retouch is a type of enhance)
'on last place in sprint that hurt' is the wordplay.
'on' becomes 're' ('on' can be mean 'with reference to').
'last place in' suggests the final letters.
'that hurt' becomes 'ouch' (I've seen this before).
The final letter of 'sprint' is 't'.
're'+'t'+'ouch'='RETOUCH'
(Other definitions for retouch that I've seen before include "Correct painting" , "Repair a painting" , "Make slight improvements to (a photo/picture)" , "Improve a photo, with a pencil say" , "Fine-tune" .)