diff --git a/src/engine/server.h b/src/engine/server.h
index 55c5cc7a4..850b4f11a 100644
--- a/src/engine/server.h
+++ b/src/engine/server.h
@@ -204,6 +204,7 @@ public:
 	virtual void GetMapInfo(char *pMapName, int MapNameSize, int *pMapSize, SHA256_DIGEST *pSha256, int *pMapCrc) = 0;
 
 	virtual bool WouldClientNameChange(int ClientID, const char *pNameRequest) = 0;
+	virtual bool WouldClientClanChange(int ClientID, const char *pClanRequest) = 0;
 	virtual void SetClientName(int ClientID, const char *pName) = 0;
 	virtual void SetClientClan(int ClientID, const char *pClan) = 0;
 	virtual void SetClientCountry(int ClientID, int Country) = 0;
diff --git a/src/engine/server/server.cpp b/src/engine/server/server.cpp
index 06daf4195..359363a69 100644
--- a/src/engine/server/server.cpp
+++ b/src/engine/server/server.cpp
@@ -452,11 +452,57 @@ bool CServer::SetClientNameImpl(int ClientID, const char *pNameRequest, bool Set
 	return Changed;
 }
 
+bool CServer::SetClientClanImpl(int ClientID, const char *pClanRequest, bool Set)
+{
+	dbg_assert(0 <= ClientID && ClientID < MAX_CLIENTS, "invalid client id");
+	if(m_aClients[ClientID].m_State < CClient::STATE_READY)
+		return false;
+
+	const CNameBan *pBanned = m_NameBans.IsBanned(pClanRequest);
+	if(pBanned)
+	{
+		if(m_aClients[ClientID].m_State == CClient::STATE_READY && Set)
+		{
+			char aBuf[256];
+			if(pBanned->m_aReason[0])
+			{
+				str_format(aBuf, sizeof(aBuf), "Kicked (your clan is banned: %s)", pBanned->m_aReason);
+			}
+			else
+			{
+				str_copy(aBuf, "Kicked (your clan is banned)");
+			}
+			Kick(ClientID, aBuf);
+		}
+		return false;
+	}
+
+	// trim the clan
+	char aTrimmedClan[MAX_CLAN_LENGTH];
+	str_copy(aTrimmedClan, str_utf8_skip_whitespaces(pClanRequest));
+	str_utf8_trim_right(aTrimmedClan);
+
+	bool Changed = str_comp(m_aClients[ClientID].m_aClan, aTrimmedClan) != 0;
+
+	if(Set)
+	{
+		// set the client clan
+		str_copy(m_aClients[ClientID].m_aClan, aTrimmedClan);
+	}
+
+	return Changed;
+}
+
 bool CServer::WouldClientNameChange(int ClientID, const char *pNameRequest)
 {
 	return SetClientNameImpl(ClientID, pNameRequest, false);
 }
 
+bool CServer::WouldClientClanChange(int ClientID, const char *pClanRequest)
+{
+	return SetClientClanImpl(ClientID, pClanRequest, false);
+}
+
 void CServer::SetClientName(int ClientID, const char *pName)
 {
 	SetClientNameImpl(ClientID, pName, true);
@@ -464,10 +510,7 @@ void CServer::SetClientName(int ClientID, const char *pName)
 
 void CServer::SetClientClan(int ClientID, const char *pClan)
 {
-	if(ClientID < 0 || ClientID >= MAX_CLIENTS || m_aClients[ClientID].m_State < CClient::STATE_READY || !pClan)
-		return;
-
-	str_copy(m_aClients[ClientID].m_aClan, pClan);
+	SetClientClanImpl(ClientID, pClan, true);
 }
 
 void CServer::SetClientCountry(int ClientID, int Country)
diff --git a/src/engine/server/server.h b/src/engine/server/server.h
index e36770edb..4c9e55922 100644
--- a/src/engine/server/server.h
+++ b/src/engine/server/server.h
@@ -296,8 +296,10 @@ public:
 
 	bool IsClientNameAvailable(int ClientID, const char *pNameRequest);
 	bool SetClientNameImpl(int ClientID, const char *pNameRequest, bool Set);
+	bool SetClientClanImpl(int ClientID, const char *pClanRequest, bool Set);
 
 	bool WouldClientNameChange(int ClientID, const char *pNameRequest) override;
+	bool WouldClientClanChange(int ClientID, const char *pClanRequest) override;
 	void SetClientName(int ClientID, const char *pName) override;
 	void SetClientClan(int ClientID, const char *pClan) override;
 	void SetClientCountry(int ClientID, int Country) override;
diff --git a/src/game/server/gamecontext.cpp b/src/game/server/gamecontext.cpp
index 154d12c90..2f7cf788b 100644
--- a/src/game/server/gamecontext.cpp
+++ b/src/game/server/gamecontext.cpp
@@ -2508,9 +2508,11 @@ void CGameContext::OnChangeInfoNetMessage(const CNetMsg_Cl_ChangeInfo *pMsg, int
 		LogEvent("Name change", ClientID);
 	}
 
-	if(str_comp(Server()->ClientClan(ClientID), pMsg->m_pClan))
+	if(Server()->WouldClientClanChange(ClientID, pMsg->m_pClan))
+	{
 		SixupNeedsUpdate = true;
-	Server()->SetClientClan(ClientID, pMsg->m_pClan);
+		Server()->SetClientClan(ClientID, pMsg->m_pClan);
+	}
 
 	if(Server()->ClientCountry(ClientID) != pMsg->m_Country)
 		SixupNeedsUpdate = true;
@@ -2717,6 +2719,11 @@ void CGameContext::OnStartInfoNetMessage(const CNetMsg_Cl_StartInfo *pMsg, int C
 		return;
 	}
 	Server()->SetClientClan(ClientID, pMsg->m_pClan);
+	// trying to set client clan can delete the player object, check if it still exists
+	if(!m_apPlayers[ClientID])
+	{
+		return;
+	}
 	Server()->SetClientCountry(ClientID, pMsg->m_Country);
 	str_copy(pPlayer->m_TeeInfos.m_aSkinName, pMsg->m_pSkin, sizeof(pPlayer->m_TeeInfos.m_aSkinName));
 	pPlayer->m_TeeInfos.m_UseCustomColor = pMsg->m_UseCustomColor;