Head to head
2
Hard
1
0
Clay
2
0
Grass
1
1
Carpet
0
Onny Parun's wins on the left · Roscoe Tanner's on the right · bar lengths share one scale
Momentum
Running lead across all meetings, oldest to newest (walkovers excluded).
All meetings (7)
| 1981 | Queen's Club | Grass | R64 | Roscoe Tanner | 6-3 6-2 |
| 1976 | South Orange | Clay | SF | Roscoe Tanner | 7-6 6-3 |
| 1976 | Johannesburg WCT | Hard | R16 | Onny Parun | 5-7 6-4 6-4 |
| 1976 | Palm Springs | Hard | R32 | Roscoe Tanner | 6-4 6-0 |
| 1975 | Stockholm-2 | Hard | QF | Onny Parun | 3-6 7-6 7-6 |
| 1974 | San Francisco | Carpet | R16 | Onny Parun | 7-6 6-3 |
| 1973 | Washington-3 | Clay | R64 | Roscoe Tanner | 6-2 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.