Most games played in a Grand Slam tennis set
- Who
- Nicolas Mahut, John Isner
- What
- 138 total number
- Where
- United Kingdom (Wimbledon, London,)
- When
- 01 January 0001
The most games played in a single set in the history of Grand Slam tennis is 138 in the fifth set of the first round Wimbledon Championships match between Nicolas Mahut (France) and John Isner (USA) in Wimbledon, London, UKfrom 23-24 June 2010.