Head to head
1
Hard
1
1
Clay
1
0
Carpet
2
Onny Parun's wins on the left · Jim Osborne's on the right · bar lengths share one scale
Momentum
Running lead across all meetings, oldest to newest (walkovers excluded).
All meetings (6)
| 1973 | San Juan | Hard | RR | Onny Parun | 7-6 6-4 |
| 1972 | Washington-1 | Carpet | R16 | Jim Osborne | 6-4 6-3 |
| 1972 | Salisbury | Carpet | R64 | Jim Osborne | 6-3 6-3 |
| 1971 | Houston | Clay | R32 | Onny Parun | 6-1 6-3 |
| 1970 | Houston | Clay | R32 | Jim Osborne | 3-6 6-4 6-3 |
| 1968 | London-2 | Hard | R16 | Jim Osborne | 6-4 6-2 5-7 6-2 |
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.