Concentrated on a point in tennis perhaps (7)
I believe the answer is:
intense
'concentrated' is the definition.
(similar in meaning)
'point in tennis perhaps' is the wordplay.
'point' becomes 'E' (compass point).
'in' is an insertion indicator.
'perhaps' is an anagram indicator.
'tennis' is an anagram of 'intnse'.
'e' put inside 'intnse' is 'INTENSE'.
'on a' is the link.
(Other definitions for intense that I've seen before include "burning" , "Feverish" , "Feeling deeply" , "Strong in quality or degree - perhaps a feeling" , "Acute, exteme" .)