One herding animals runs into port (6)
I believe the answer is:
drover
'one herding animals' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'runs into port' is the wordplay.
'runs' becomes 'r' (cricket abbreviation).
'into' is an insertion indicator.
'port' becomes 'dover' (English port).
'r' put into 'dover' is 'DROVER'.
Can you help me to learn more?
(Other definitions for drover that I've seen before include "Rural worker" , "One driving flock to market" , "One driving cattle" , "I bring along many animals" , "Herdsman" .)