| Singles | |
|---|---|
| 1991 U.S. Men's Clay Court Championships | |
| Champion |  Jaime Yzaga |
| Runner-up |  Jimmy Arias |
| Score | 6–3, 7–5 |
| Draw | 32 |
| Seeds | 8 |
David Wheaton was the defending champion, but lost in the quarterfinals this year.
Jaime Yzaga won the title, defeating Jimmy Arias 6–3, 7–5 in the final.
A champion seed is indicated in bold text while text in italics indicates the round in which that seed was eliminated.
Michael Chang (quarterfinals) Derrick Rostagno (first round) David Wheaton (quarterfinals) Richey Reneberg (quarterfinals) Jimmy Arias (final) Scott Davis (first round) Jaime Yzaga (champion) David Pate (first round)| First round | Second round | Quarterfinals | Semifinals | Final | ||||||||||||||||||||||||||||||
| 1 | M Chang | 6 | 7 | |||||||||||||||||||||||||||||||
 N Kroon | 0 | 5 | 1 | M Chang | 65 | 6 | 7 | |||||||||||||||||||||||||||
| B Shelton | 6 | 6 | B Shelton | 77 | 4 | 5 | ||||||||||||||||||||||||||||
 S Pescosolido | 2 | 2 | 1 | M Chang | 60 | 1 | ||||||||||||||||||||||||||||
 A Sznajder | 1 | 6 | 4 | 7 | J Yzaga | 77 | 6 | |||||||||||||||||||||||||||
| Q | J Brown | 6 | 3 | 6 | Q | J Brown | 4 | 4 | ||||||||||||||||||||||||||
| C Garner | 66 | 3 | 7 | J Yzaga | 6 | 6 | ||||||||||||||||||||||||||||
| 7 | J Yzaga | 78 | 6 | 7 | J Yzaga | 7 | 6 | |||||||||||||||||||||||||||
| 3 | D Wheaton | 6 | 6 | M Washington | 5 | 2 | ||||||||||||||||||||||||||||
| C Adams | 4 | 3 | 3 | D Wheaton | 6 | 6 | ||||||||||||||||||||||||||||
| WC | J Pugh | 1 | 3 |  P Korda | 3 | 4 | ||||||||||||||||||||||||||||
| P Korda | 6 | 6 | 3 | D Wheaton | 77 | 1 | 2 | |||||||||||||||||||||||||||
| WC | R Leach | 1 | 64 | M Washington | 63 | 6 | 6 | |||||||||||||||||||||||||||
| M Washington | 6 | 77 | M Washington | 6 | 6 | |||||||||||||||||||||||||||||
 C Saceanu | 6 | 3 | 6 | C Saceanu | 3 | 4 | ||||||||||||||||||||||||||||
| 6 | S Davis | 1 | 6 | 0 | 7 | Jaime Yzaga | 6 | 7 | ||||||||||||||||||||||||||
| 5 | J Arias | 6 | 6 | 5 | Jimmy Arias | 3 | 5 | |||||||||||||||||||||||||||
| T Högstedt | 3 | 3 | 5 | J Arias | 6 | 6 | ||||||||||||||||||||||||||||
| J Tarango | 4 | 2 |  D Pérez | 1 | 4 | |||||||||||||||||||||||||||||
| D Pérez | 6 | 6 | 5 | J Arias | 6 | 6 | ||||||||||||||||||||||||||||
| WC | M Pernfors | 4 | 4 | 4 | R Reneberg | 4 | 2 | |||||||||||||||||||||||||||
| Q | M Wostenholme | 6 | 6 | Q | M Wostenholme | 6 | 0 | 3 | ||||||||||||||||||||||||||
| Q |  R Viver | 4 | 5 | 4 | R Reneberg | 4 | 6 | 6 | ||||||||||||||||||||||||||
| 4 | R Reneberg | 6 | 7 | 5 | J Arias | 3 | 6 | 7 | ||||||||||||||||||||||||||
| 8 | D Pate | 6 | 3 | 63 | Q |  J Frana | 6 | 3 | 5 | |||||||||||||||||||||||||
| B Pearce | 3 | 6 | 77 | B Pearce | 4 | 2 | ||||||||||||||||||||||||||||
| B Garrow | 63 | 3 | Q | J Frana | 6 | 6 | ||||||||||||||||||||||||||||
| Q | J Frana | 77 | 6 | Q | J Frana | 6 | ||||||||||||||||||||||||||||
| D Nargiso | 6 | 77 | P Arraya | 4 | r | |||||||||||||||||||||||||||||
 K Evernden | 2 | 63 | D Nargiso | 6 | 4 | 63 | ||||||||||||||||||||||||||||
| P Arraya | 77 | 6 | P Arraya | 2 | 6 | 77 | ||||||||||||||||||||||||||||
| 2 | D Rostagno | 63 | 3 | |||||||||||||||||||||||||||||||
Thomas Enqvist was the defending champion but lost in the second round to Jaime Yzaga.
Jay Berger was the defending champion, but did not participate this year.
Jaime Yzaga was the defending champion, but lost in the first round this year.
MaliVai Washington was the defending champion, but lost in the first round this year.
Andre Agassi defeated Jason Stoltenberg in the final, 6–4, 6–4 to win the men's singles tennis title at the 1994 Canadian Open.
Defending champion Andre Agassi defeated Pete Sampras in the final, 3–6, 6–2, 6–3 to win the men's singles tennis title at the 1995 Canadian Open.
Jaime Yzaga was the defending champion but lost in the first round to Aaron Krickstein.
Joakim Nyström was the defending champion but did not compete that year.
John McEnroe was the defending champion but lost in the semifinals to Boris Becker.
Mark Kratzmann and Wally Masur were the defending champions but only Masur competed that year with Pat Cash.
Luiz Mattar was the defending champion and won in the final 7–6, 6–4 against Jimmy Brown.
Ricardo Acuña and Luke Jensen were the defending champions but did not compete that year.
Andre Agassi was the defending champion but lost in the semifinals to Ivan Lendl.
Pete Sampras defeated Andrés Gómez in the final, 7–6(7–4), 7–5, 6–2 to win the singles tennis title at the 1990 Ebel U.S. Pro Indoor. It was his maiden singles title.
Joakim Nyström was the champion of the event when it last took place, in 1986. He did not participate in 1990.
Ivan Lendl won the title, defeating Tim Mayotte 6–3, 6–0, in the final.
José Luis Clerc was the defending champion, but lost to José Higueras in the semifinals. Fifth seed Higueras defeated Jimmy Arias in the final to claim the title and first prize money of $32,000.
Andre Agassi was the defending champion and successfully defended his title, by defeating Petr Korda 6–3, 6–4 in the final.
Yannick Noah was the defending champion, but did not compete this year.
Karel Nováček was the defending champion, but chose to compete at Hilversum during the same week.