Cincinnati 1991 • ATP Masters 1000 — Quadro
5 — 11 agosto
- USAx22
- Australiax5
- South Africax5
- Swedenx5
- Francex3
- Italyx3
- Israelx2
- Russiax2
- Brazilx1
- Canadax1
- Czech Republicx1
- Ecuadorx1
- Spainx1
- Germanyx1
- Indiax1
- Perux1
- Switzerlandx1
- USAx12
- South Africax4
- Swedenx4
- Australiax2
- Francex2
- Czech Republicx1
- Ecuadorx1
- Germanyx1
- Israelx1
- Italyx1
- Perux1
- Russiax1
- Switzerlandx1
- USAx9
- Francex1
- Germanyx1
- Israelx1
- Italyx1
- South Africax1
- Russiax1
- Swedenx1
- USAx4
- Francex1
- Germanyx1
- Russiax1
- Swedenx1