Head to head
4
Hard
2
1
Clay
0
0
Grass
1
1
Carpet
0
Mark Cox's wins on the left · Robert Lutz's on the right · bar lengths share one scale
Momentum
Running lead across all meetings, oldest to newest (walkovers excluded).
All meetings (9)
| 1980 | Johannesburg-2 | Hard | R32 | Robert Lutz | 4-6 6-1 6-3 |
| 1975 | Fort Worth WCT | Hard | R32 | Mark Cox | 6-4 6-4 |
| 1974 | Philadelphia WCT | Carpet | R16 | Mark Cox | 6-3 6-1 |
| 1971 | Fort Worth WCT | Hard | R32 | Robert Lutz | 6-2 3-6 7-5 |
| 1971 | Toronto WCT | Clay | R32 | Mark Cox | 6-2 6-1 |
| 1971 | Australian Open | Grass | QF | Robert Lutz | 6-2 6-1 6-2 |
| 1970 | Boston | Hard | R32 | Mark Cox | 6-3 6-7 6-4 |
| 1969 | Salisbury | Hard | R16 | Mark Cox | 4-6 6-4 6-4 |
| 1968 | London-3 | Hard | SF | Mark Cox | 6-4 6-4 |
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.