Head to head
2
Clay
1
1
Grass
0
Guillermo Vilas's wins on the left · John Alexander's on the right · bar lengths share one scale
All meetings (4)
| 1979 | Monte-Carlo WCT | Clay | R16 | John Alexander | 4-6 7-6 7-6 |
| 1977 | Davis Cup EUR SF: ARG vs AUS | Clay | RR | Guillermo Vilas | 6-4 7-5 4-6 6-2 |
| 1977 | Australian Open-1 | Grass | SF | Guillermo Vilas | 6-4 1-6 6-3 6-4 |
| 1973 | Louisville | Clay | R16 | Guillermo Vilas | 6-2 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.