Head to head
1
Hard
0
1
Clay
0
1
Carpet
1
Clark Graebner's wins on the left · Juan Gisbert Sr's on the right · bar lengths share one scale
All meetings (4)
| 1972 | New York-1 | Carpet | R32 | Juan Gisbert Sr | 4-6 6-4 6-2 |
| 1971 | Kitzbuhel | Clay | QF | Clark Graebner | 7-6 1-6 7-6 3-6 6-2 |
| 1971 | Macon | Carpet | R16 | Clark Graebner | 7-5 4-6 6-2 |
| 1968 | Davis Cup EUR SF: USA vs ESP | Hard | RR | Clark Graebner | 9-7 6-3 6-1 |
Methodology
Head-to-head totals and surface splits exclude walkovers (no match was played), which follows ATP convention — walkover meetings still appear in the match list. The momentum chart plots the running lead across all counted meetings, oldest to newest.