1991 ATP Championship Series, Single Week Singles Singles

| Tournament | Surface | Week | Winner_and_score | Finalist | Semifinalists |
|---|---|---|---|---|---|
| Montréal | Hard | July 22 | Andrei Chesnokov 3–6, 6–4, 6–3 | Petr Korda | Ivan Lendl Jim Courier |
| Cincinnati | Hard | August 5 | Guy Forget 2–6, 7–6(4), 6–4 | Pete Sampras | Boris Becker Jim Courier |
| Stockholm | Carpet (i) | October 21 | Boris Becker 3–6, 6–4, 1–6, 6–2, 6–2 | Stefan Edberg | Aaron Krickstein Jim Courier |
| Paris | Carpet (i) | October 28 | Guy Forget 7–6(9), 4–6, 5–7, 6–4, 6–4 | Pete Sampras | Michael Chang Jonas Svensson |