One new ball yields odd runs; hassled (7)
I believe the answer is:
annoyed
'runs hassled' is the definition.
I can't tell whether this defines the answer.
'one new ball yields odd' is the wordplay.
'one' becomes 'an' ('a' and 'an' can mean 'one').
'new' becomes 'n' (common abbreviation eg NT for New Testament).
'ball' becomes 'o' (letter resembling a ball).
'odd' means one should take alternating letters.
The alternate letters of 'yields' are 'yed'.
'an'+'n'+'o'+'yed'='ANNOYED'
Can you help me to learn more?
(Other definitions for annoyed that I've seen before include "Irate" , "Irritated, peeved" , "put out" , "Displeased" , "'Irritated, impatient (7)'" .)