Head to head
1
Clay
0
1
Grass
0
1
Carpet
1
John Alexander's wins on the left · Heinz Gunthardt's on the right · bar lengths share one scale
All meetings (4)
| 1984 | Luxembourg | Carpet | R32 | Heinz Gunthardt | 7-5 6-7 7-5 |
| 1979 | Wimbledon | Grass | R64 | John Alexander | 6-3 3-6 5-7 6-3 6-2 |
| 1978 | North Conway | Clay | QF | John Alexander | 6-4 6-4 |
| 1978 | Birmingham WCT | Carpet | R32 | John Alexander | 6-3 7-5 |
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.