Fix crash

tournaments/models/tournament.py

@@ -94,7 +94,11 @@ class Tournament(models.Model):
         return f"{self.level()} {self.category()}"
 
     def short_base_name(self):
-        return f"{self.level()}{self.category()[0]}"
+        category = self.category()
+        if len(category) > 0:
+            return f"{self.level()}{category[0]}"
+        else:
+            return self.level()
 
     def filter_name(self):
         components = [self.formatted_start_date(), self.short_base_name()]