diff --git a/Shogi.Api/Controllers/SessionsController.cs b/Shogi.Api/Controllers/SessionsController.cs
index 75614aa..9e72c63 100644
--- a/Shogi.Api/Controllers/SessionsController.cs
+++ b/Shogi.Api/Controllers/SessionsController.cs
@@ -118,7 +118,7 @@ public class SessionsController : ControllerBase
             session.AddPlayer2(User.GetShogiUserId());
 
             await sessionRepository.SetPlayer2(name, User.GetShogiUserId());
-            await communicationManager.BroadcastToAll(new SessionJoinedByPlayerSocketMessage());
+            await communicationManager.BroadcastToAll(new SessionJoinedByPlayerSocketMessage(session.Name));
             return this.Ok();
         }
         return this.Conflict("This game already has two players.");
diff --git a/Shogi.Contracts/Socket/SessionJoinedByPlayerSocketMessage.cs b/Shogi.Contracts/Socket/SessionJoinedByPlayerSocketMessage.cs
index 70fc4bf..d6c8f53 100644
--- a/Shogi.Contracts/Socket/SessionJoinedByPlayerSocketMessage.cs
+++ b/Shogi.Contracts/Socket/SessionJoinedByPlayerSocketMessage.cs
@@ -1,9 +1,15 @@
 using Shogi.Contracts.Types;
 
-namespace Shogi.Contracts.Socket
+namespace Shogi.Contracts.Socket;
+
+public class SessionJoinedByPlayerSocketMessage : ISocketResponse
 {
-    public class SessionJoinedByPlayerSocketMessage : ISocketResponse
+    public SocketAction Action => SocketAction.SessionJoined;
+
+    public string SessionName { get; }
+
+    public SessionJoinedByPlayerSocketMessage(string sessionName)
     {
-        public SocketAction Action => SocketAction.SessionJoined;
+        SessionName = sessionName;
     }
 }
diff --git a/Shogi.UI/Pages/Home/GameBoard/GameBoard.razor b/Shogi.UI/Pages/Home/GameBoard/GameBoard.razor
index def4991..d7e316e 100644
--- a/Shogi.UI/Pages/Home/GameBoard/GameBoard.razor
+++ b/Shogi.UI/Pages/Home/GameBoard/GameBoard.razor
@@ -13,7 +13,7 @@
 }
 else if (isSpectating)
 {
-    <SpectatorGameBoard Session="session" OnRefetchSession="RefetchSession" />
+    <SpectatorGameBoard Session="session" />
 }
 else
 {
@@ -32,16 +32,25 @@ else
     protected override void OnInitialized()
     {
         base.OnInitialized();
-        ShogiSocket.OnPlayerMoved += OnPlayerMoved_RefetchSession;
-        ShogiSocket.OnSessionJoined += 
+        ShogiSocket.OnPlayerMoved += OnPlayerMoved_FetchSession;
+        ShogiSocket.OnSessionJoined += OnSessionJoined_FetchSession;
     }
 
     protected override async Task OnParametersSetAsync()
     {
-        await RefetchSession();
+        await FetchSession();
     }
 
-    async Task RefetchSession()
+    Task OnSessionJoined_FetchSession(SessionJoinedByPlayerSocketMessage args)
+    {
+        if (args.SessionName == SessionName)
+        {
+            return FetchSession();
+        }
+        return Task.CompletedTask;
+    }
+
+    async Task FetchSession()
     {
         if (!string.IsNullOrWhiteSpace(SessionName))
         {
@@ -59,11 +68,11 @@ else
         }
     }
 
-    Task OnPlayerMoved_RefetchSession(PlayerHasMovedMessage args)
+    Task OnPlayerMoved_FetchSession(PlayerHasMovedMessage args)
     {
         if (args.SessionName == SessionName)
         {
-            return RefetchSession();
+            return FetchSession();
         }
         return Task.CompletedTask;
     }
diff --git a/Shogi.UI/Pages/Home/GameBrowser.razor b/Shogi.UI/Pages/Home/GameBrowser.razor
index 886d39e..8ccdaf6 100644
--- a/Shogi.UI/Pages/Home/GameBrowser.razor
+++ b/Shogi.UI/Pages/Home/GameBrowser.razor
@@ -1,5 +1,6 @@
 @implements IDisposable;
 
+@using Shogi.Contracts.Socket;
 @using Shogi.Contracts.Types;
 @using System.ComponentModel.DataAnnotations;
 @using System.Net;
@@ -98,7 +99,7 @@
     {
         base.OnInitialized();
         ShogiSocket.OnSessionCreated += FetchSessions;
-        ShogiSocket.OnSessionJoined += FetchSessions;
+        ShogiSocket.OnSessionJoined += OnSessionJoined_FetchSessions;
         Account.LoginChangedEvent += LoginChangedEvent_FetchSessions;
     }
 
@@ -109,6 +110,9 @@
         activeSession = s;
         ActiveSessionChanged?.Invoke(s);
     }
+
+    Task OnSessionJoined_FetchSessions(SessionJoinedByPlayerSocketMessage args) => FetchSessions();
+
     Task LoginChangedEvent_FetchSessions(LoginEventArgs args)
     {
         if (args.User != null)
@@ -137,7 +141,7 @@
     public void Dispose()
     {
         ShogiSocket.OnSessionCreated -= FetchSessions;
-        ShogiSocket.OnSessionJoined -= FetchSessions;
+        ShogiSocket.OnSessionJoined -= OnSessionJoined_FetchSessions;
         Account.LoginChangedEvent -= LoginChangedEvent_FetchSessions;
     }
 
diff --git a/Shogi.UI/Shared/ShogiSocket.cs b/Shogi.UI/Shared/ShogiSocket.cs
index ea01560..0913225 100644
--- a/Shogi.UI/Shared/ShogiSocket.cs
+++ b/Shogi.UI/Shared/ShogiSocket.cs
@@ -11,7 +11,7 @@ namespace Shogi.UI.Shared;
 public class ShogiSocket : IDisposable
 {
     public event AsyncEventHandler? OnSessionCreated;
-    public event AsyncEventHandler? OnSessionJoined;
+    public event AsyncEventHandler<SessionJoinedByPlayerSocketMessage>? OnSessionJoined;
     public event AsyncEventHandler<PlayerHasMovedMessage>? OnPlayerMoved;
 
     private readonly ClientWebSocket socket;
@@ -76,7 +76,8 @@ public class ShogiSocket : IDisposable
                 case SocketAction.SessionJoined:
                     if (this.OnSessionJoined is not null)
                     {
-                        await this.OnSessionJoined();
+                        var args = JsonSerializer.Deserialize<SessionJoinedByPlayerSocketMessage>(memory[..result.Count], serializerOptions);
+                        await this.OnSessionJoined(args!);
                     }
                     break;
                 case SocketAction.PieceMoved: