diff --git a/socketserver/internal/server/commands.go b/socketserver/internal/server/commands.go
index ee819650..db91c66a 100644
--- a/socketserver/internal/server/commands.go
+++ b/socketserver/internal/server/commands.go
@@ -85,22 +85,20 @@ func HandleReady(conn *websocket.Conn, client *ClientInfo, msg ClientMessage) (r
 	client.MakePendingRequests = nil
 	client.Mutex.Unlock()
 
-	if disconnectAt == 0 {
-		// backlog only
-		go func() {
-			client.MessageChannel <- ClientMessage{MessageID: msg.MessageID, Command: SuccessCommand}
-			SendBacklogForNewClient(client)
-		}()
-		return ClientMessage{Command: AsyncResponseCommand}, nil
-	} else {
-		// backlog and timed
-		go func() {
-			client.MessageChannel <- ClientMessage{MessageID: msg.MessageID, Command: SuccessCommand}
-			SendBacklogForNewClient(client)
+	go func() {
+		client.MsgChannelKeepalive.RLock()
+		if client.MessageChannel == nil {
+			return
+		}
+
+		client.MessageChannel <- ClientMessage{MessageID: msg.MessageID, Command: SuccessCommand}
+		SendBacklogForNewClient(client)
+		if disconnectAt != 0 {
 			SendTimedBacklogMessages(client, time.Unix(disconnectAt, 0))
-		}()
-		return ClientMessage{Command: AsyncResponseCommand}, nil
-	}
+		}
+		client.MsgChannelKeepalive.RUnlock()
+	}()
+	return ClientMessage{Command: AsyncResponseCommand}, nil
 }
 
 func HandleSetUser(conn *websocket.Conn, client *ClientInfo, msg ClientMessage) (rmsg ClientMessage, err error) {
@@ -193,9 +191,13 @@ func GetSubscriptionBacklog(conn *websocket.Conn, client *ClientInfo) {
 	}
 
 	// Deliver to client
-	for _, msg := range messages {
-		client.MessageChannel <- msg
+	client.MsgChannelKeepalive.RLock()
+	if client.MessageChannel != nil {
+		for _, msg := range messages {
+			client.MessageChannel <- msg
+		}
 	}
+	client.MsgChannelKeepalive.RUnlock()
 }
 
 func HandleSurvey(conn *websocket.Conn, client *ClientInfo, msg ClientMessage) (rmsg ClientMessage, err error) {
@@ -318,11 +320,15 @@ func HandleRemoteCommand(conn *websocket.Conn, client *ClientInfo, msg ClientMes
 	go func(conn *websocket.Conn, msg ClientMessage, authInfo AuthInfo) {
 		resp, err := RequestRemoteDataCached(string(msg.Command), msg.origArguments, authInfo)
 
-		if err != nil {
-			client.MessageChannel <- ClientMessage{MessageID: msg.MessageID, Command: ErrorCommand, Arguments: err.Error()}
-		} else {
-			client.MessageChannel <- ClientMessage{MessageID: msg.MessageID, Command: SuccessCommand, origArguments: resp}
+		client.MsgChannelKeepalive.RLock()
+		if client.MessageChannel != nil {
+			if err != nil {
+				client.MessageChannel <- ClientMessage{MessageID: msg.MessageID, Command: ErrorCommand, Arguments: err.Error()}
+			} else {
+				client.MessageChannel <- ClientMessage{MessageID: msg.MessageID, Command: SuccessCommand, origArguments: resp}
+			}
 		}
+		client.MsgChannelKeepalive.RUnlock()
 	}(conn, msg, client.AuthInfo)
 
 	return ClientMessage{Command: AsyncResponseCommand}, nil
diff --git a/socketserver/internal/server/handlecore.go b/socketserver/internal/server/handlecore.go
index 1a61b0ef..c2d05ce8 100644
--- a/socketserver/internal/server/handlecore.go
+++ b/socketserver/internal/server/handlecore.go
@@ -247,6 +247,10 @@ RunLoop:
 	// Stop getting messages...
 	UnsubscribeAll(&client)
 
+	client.MsgChannelKeepalive.Lock()
+	client.MessageChannel = nil
+	client.MsgChannelKeepalive.Unlock()
+
 	// And finished.
 	// Close the channel so the draining goroutine can finish, too.
 	close(_serverMessageChan)
diff --git a/socketserver/internal/server/types.go b/socketserver/internal/server/types.go
index d3d1224e..0fd79a39 100644
--- a/socketserver/internal/server/types.go
+++ b/socketserver/internal/server/types.go
@@ -85,9 +85,12 @@ type ClientInfo struct {
 	MakePendingRequests *time.Timer
 
 	// Server-initiated messages should be sent here
-	// Never nil.
+	// This field will be nil before it is closed.
 	MessageChannel chan<- ClientMessage
 
+	// Take a read-lock on this before checking whether MessageChannel is nil.
+	MsgChannelKeepalive sync.RWMutex
+
 	// The number of pings sent without a response
 	pingCount int
 }