diff --git a/CommonCore/SQL/src/de/steamwar/sql/Team.kt b/CommonCore/SQL/src/de/steamwar/sql/Team.kt
index 0c56a656..2738170b 100644
--- a/CommonCore/SQL/src/de/steamwar/sql/Team.kt
+++ b/CommonCore/SQL/src/de/steamwar/sql/Team.kt
@@ -43,10 +43,10 @@ class Team(id: EntityID<Int>) : IntEntity(id) {
         private val teamCache = mutableMapOf<Int, Team>()
 
         @JvmStatic
-        fun clear() = teamCache.clear()
+        fun clear() = synchronized(teamCache) { teamCache.clear() }
 
         @JvmStatic
-        fun byId(id: Int) = teamCache.computeIfAbsent(id) { useDb { Team[id] } }
+        fun byId(id: Int) = synchronized(teamCache) { teamCache.computeIfAbsent(id) { useDb { Team[id] } } }
 
         @JvmStatic
         fun get(name: String) = useDb { find { TeamTable.name.lowerCase() eq name.lowercase() or (TeamTable.kuerzel.lowerCase() eq name.lowercase()) }.firstOrNull() }