| KNVB beker 1969/1970 - Appearances as Referee |  |
 |
 |
||||
| 19/10/1969 | Hermes/DVS | - | SC Veendam | 2:0 | - | - | - |
| 01/03/1970 | Go Ahead | - | RBC Roosendaal | 3:0 | - | - | - |
| KNVB beker 1969/1970 - Appearances as Referee | |
|
|
||||
| 19/10/1969 | Hermes/DVS | - | SC Veendam | 2:0 | - | - | - |
| 01/03/1970 | Go Ahead | - | RBC Roosendaal | 3:0 | - | - | - |
| Complete name: | Johannes Nicolaus Ignacius Keizer |
| Born: | 06/10/1940 |
| Place of birth: |
Volendam, 
Netherlands |
| Nationality: |
Netherlands |