diff --git a/src/main/java/nl/connectedit/swiss/service/RegistrationService.java b/src/main/java/nl/connectedit/swiss/service/RegistrationService.java
index 761eeb7..d5df5d6 100644
--- a/src/main/java/nl/connectedit/swiss/service/RegistrationService.java
+++ b/src/main/java/nl/connectedit/swiss/service/RegistrationService.java
@@ -53,7 +53,9 @@ public class RegistrationService {
   private void removeEventFromTournamentPlayer(Tournament tournament, Player player, Event event) {
     var tournamentPlayer = findOrAddTournamentPlayer(tournament, player);
     tournamentPlayer.getEvents().removeIf(eventType -> eventType.equals(event.getType().name()));
-    tournamentPlayer.getSubstitutions().removeIf(substitution -> substitution.getEvent().equals(event));
+    if (tournamentPlayer.getSubstitutions() != null) {
+      tournamentPlayer.getSubstitutions().removeIf(substitution -> substitution.getEvent().equals(event));
+    }
   }
 
   private void addEventToTournamentPlayer(Tournament tournament, Player player, Event event) {