Match at Roland Garros in summer? (9)
I believe the answer is:
encounter
'match' is the definition.
(thesaurus)
'at roland garros in summer?' is the wordplay.
'at roland garros in' becomes 'en' ('at' in French - Roland-Garros is the French Open).
'summer?' becomes 'counter' (someone who counts or does sums).
'en'+'counter'='ENCOUNTER'
(Other definitions for encounter that I've seen before include "fight" , "Meet; confrontation" , "tackle" , "Come accross, meet (9)" , "Run into - combat" .)