They might run around a lawn with rackets? Cash ultimately with advantage first (9)

'they might run around a lawn' is the definition.
(row of hedges which might border a lawn)

'rackets? cash ultimately with advantage first' is the wordplay.
'rackets?' becomes 'rows' (I've seen this before).
'ultimately' says to take the final letters.
'with' is a charade indicator (letters next to each other).
'advantage' becomes 'edge' (edge is a kind of advantage).
'first' is a charade indicator (letters next to each other).
The last letter of 'cash' is 'h'.
'h'+'edge' is 'hedge'.
'rows' put after 'hedge' is 'HEDGEROWS'.

'with' is the link.