| Men's Singles | |
|---|---|
| 2013 Western & Southern Open | |
| Champion |
|
| Runner-up |
|
| Final score | 7–6(10–8), 7–6(7–3) |
Roger Federer was the defending champion, but was defeated in the quarterfinals by Rafael Nadal who went on to win his first ever Cincinnati Open title and record-extending 26th ATP World Tour Masters 1000.
The top eight seeds receive a bye into the second round.