- Who
- John Isner, Nicolas Mahut
- What
- 138 total number
- Where
- United Kingdom (Wimbledon, London)
- When
The most games played in a single set in the history of professional 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, UK, from 23-24 June 2010.