diff --git a/test/IntegrationTests/MSTest.Acceptance.IntegrationTests/JUnitReportTests.cs b/test/IntegrationTests/MSTest.Acceptance.IntegrationTests/JUnitReportTests.cs
index efda20786e..32251577aa 100644
--- a/test/IntegrationTests/MSTest.Acceptance.IntegrationTests/JUnitReportTests.cs
+++ b/test/IntegrationTests/MSTest.Acceptance.IntegrationTests/JUnitReportTests.cs
@@ -100,6 +100,7 @@ public override (string ID, string Name, string Code) GetAssetsToGenerate() => (
   </PropertyGroup>
 
   <ItemGroup>
+    <PackageReference Include="Microsoft.Testing.Platform" Version="$MicrosoftTestingPlatformVersion$" />
     <PackageReference Include="MSTest" Version="$MSTestVersion$" />
     <PackageReference Include="Microsoft.Testing.Extensions.JUnitReport" Version="$MicrosoftTestingExtensionsJUnitReportVersion$" />
   </ItemGroup>
@@ -233,6 +234,7 @@ public override (string ID, string Name, string Code) GetAssetsToGenerate() => (
   </PropertyGroup>
 
   <ItemGroup>
+    <PackageReference Include="Microsoft.Testing.Platform" Version="$MicrosoftTestingPlatformVersion$" />
     <PackageReference Include="MSTest" Version="$MSTestVersion$" />
     <PackageReference Include="Microsoft.Testing.Extensions.JUnitReport" Version="$MicrosoftTestingExtensionsJUnitReportVersion$" />
     <PackageReference Include="Microsoft.Testing.Extensions.Retry" Version="$MicrosoftTestingPlatformVersion$" />
diff --git a/test/IntegrationTests/MSTest.Acceptance.IntegrationTests/TelemetryTests.cs b/test/IntegrationTests/MSTest.Acceptance.IntegrationTests/TelemetryTests.cs
index bf099284bc..940fb2c83c 100644
--- a/test/IntegrationTests/MSTest.Acceptance.IntegrationTests/TelemetryTests.cs
+++ b/test/IntegrationTests/MSTest.Acceptance.IntegrationTests/TelemetryTests.cs
@@ -26,7 +26,7 @@ public sealed class TelemetryTests : AcceptanceTestBase<TelemetryTests.TestAsset
     public async Task MTP_RunTests_SendsTelemetryWithSettingsAndAttributes(string tfm)
     {
         string diagPath = Path.Combine(AssetFixture.MTPProjectPath, "bin", "Release", tfm, TestResultsFolderName);
-        string diagPathPattern = Path.Combine(diagPath, @"log_.*.diag").Replace(@"\", @"\\");
+        string diagPathPattern = BuildDefaultDiagnosticFilePathPattern(diagPath, tfm);
 
         var testHost = TestHost.LocateFrom(AssetFixture.MTPProjectPath, MTPAssetName, tfm);
         TestHostResult testHostResult = await testHost.ExecuteAsync(
@@ -66,7 +66,7 @@ public async Task MTP_RunTests_SendsTelemetryWithSettingsAndAttributes(string tf
     public async Task MTP_DiscoverTests_SendsTelemetryEvent(string tfm)
     {
         string diagPath = Path.Combine(AssetFixture.MTPProjectPath, "bin", "Release", tfm, TestResultsFolderName);
-        string diagPathPattern = Path.Combine(diagPath, @"log_.*.diag").Replace(@"\", @"\\");
+        string diagPathPattern = BuildDefaultDiagnosticFilePathPattern(diagPath, tfm);
 
         var testHost = TestHost.LocateFrom(AssetFixture.MTPProjectPath, MTPAssetName, tfm);
         TestHostResult testHostResult = await testHost.ExecuteAsync(
@@ -92,7 +92,7 @@ public async Task MTP_DiscoverTests_SendsTelemetryEvent(string tfm)
     public async Task MTP_WhenTelemetryDisabled_DoesNotSendMSTestEvent(string tfm)
     {
         string diagPath = Path.Combine(AssetFixture.MTPProjectPath, "bin", "Release", tfm, TestResultsFolderName);
-        string diagPathPattern = Path.Combine(diagPath, @"log_.*.diag").Replace(@"\", @"\\");
+        string diagPathPattern = BuildDefaultDiagnosticFilePathPattern(diagPath, tfm);
 
         var testHost = TestHost.LocateFrom(AssetFixture.MTPProjectPath, MTPAssetName, tfm);
         TestHostResult testHostResult = await testHost.ExecuteAsync(
@@ -195,6 +195,17 @@ private static async Task<string> AssertDiagnosticReportAsync(TestHostResult tes
         return (Regex.IsMatch(content, pattern), content);
     }
 
+    // Build a regex matching the deterministic default diagnostic file name shape:
+    // "<asset-name>_<tfm>_<arch>_<yyMMddHHmmssfff>.diag". The arch token is taken from the
+    // current process (the testhost runs on the same machine, so its ProcessArchitecture matches).
+    private static string BuildDefaultDiagnosticFilePathPattern(string diagPath, string tfm)
+    {
+        string arch = RuntimeInformation.ProcessArchitecture.ToString().ToLowerInvariant();
+        const string FileNamePlaceholder = "__DIAG_FILENAME__";
+        string combinedPath = Path.Combine(diagPath, FileNamePlaceholder).Replace(@"\", @"\\");
+        return combinedPath.Replace(FileNamePlaceholder, $@"{MTPAssetName}_{Regex.Escape(tfm)}_{arch}_\d{{15}}\.diag");
+    }
+
     #endregion
 
     public sealed class TestAssetFixture() : TestAssetFixtureBase()
diff --git a/test/IntegrationTests/Microsoft.Testing.Platform.Acceptance.IntegrationTests/TelemetryDisabledTests.cs b/test/IntegrationTests/Microsoft.Testing.Platform.Acceptance.IntegrationTests/TelemetryDisabledTests.cs
index a025b50d32..4197891766 100644
--- a/test/IntegrationTests/Microsoft.Testing.Platform.Acceptance.IntegrationTests/TelemetryDisabledTests.cs
+++ b/test/IntegrationTests/Microsoft.Testing.Platform.Acceptance.IntegrationTests/TelemetryDisabledTests.cs
@@ -15,7 +15,7 @@ public sealed class TelemetryDisabledTests : AcceptanceTestBase<TelemetryDisable
     public async Task Telemetry_WhenEnableTelemetryIsFalse_WithTestApplicationOptions_TelemetryIsDisabled(string tfm)
     {
         string diagPath = Path.Combine(AssetFixture.TargetAssetPath, "bin", "Release", tfm, AggregatedConfiguration.DefaultTestResultFolderName);
-        string diagPathPattern = Path.Combine(diagPath, @"log_.*.diag").Replace(@"\", @"\\");
+        string diagPathPattern = BuildDefaultDiagnosticFilePathPattern(diagPath, tfm);
 
         var testHost = TestInfrastructure.TestHost.LocateFrom(AssetFixture.TargetAssetPath, AssetName, tfm);
         TestHostResult testHostResult = await testHost.ExecuteAsync("--diagnostic", disableTelemetry: false, cancellationToken: TestContext.CancellationToken);
@@ -55,6 +55,17 @@ private static async Task<string> AssertDiagnosticReportAsync(TestHostResult tes
         return (Regex.IsMatch(content, pattern), content);
     }
 
+    // Build a regex matching the deterministic default diagnostic file name shape:
+    // "<asset-name>_<tfm>_<arch>_<yyMMddHHmmssfff>.diag". The arch token is taken from the
+    // current process (the testhost runs on the same machine, so its ProcessArchitecture matches).
+    private static string BuildDefaultDiagnosticFilePathPattern(string diagPath, string tfm)
+    {
+        string arch = RuntimeInformation.ProcessArchitecture.ToString().ToLowerInvariant();
+        const string FileNamePlaceholder = "__DIAG_FILENAME__";
+        string combinedPath = Path.Combine(diagPath, FileNamePlaceholder).Replace(@"\", @"\\");
+        return combinedPath.Replace(FileNamePlaceholder, $@"{AssetName}_{Regex.Escape(tfm)}_{arch}_\d{{15}}\.diag");
+    }
+
     public sealed class TestAssetFixture() : TestAssetFixtureBase()
     {
         private const string WithoutTelemetry = nameof(WithoutTelemetry);
diff --git a/test/IntegrationTests/Microsoft.Testing.Platform.Acceptance.IntegrationTests/TelemetryTests.cs b/test/IntegrationTests/Microsoft.Testing.Platform.Acceptance.IntegrationTests/TelemetryTests.cs
index 0272637c43..f8ae989fec 100644
--- a/test/IntegrationTests/Microsoft.Testing.Platform.Acceptance.IntegrationTests/TelemetryTests.cs
+++ b/test/IntegrationTests/Microsoft.Testing.Platform.Acceptance.IntegrationTests/TelemetryTests.cs
@@ -15,7 +15,7 @@ public class TelemetryTests : AcceptanceTestBase<TelemetryTests.TestAssetFixture
     public async Task Telemetry_ByDefault_TelemetryIsEnabled(string tfm)
     {
         string diagPath = Path.Combine(AssetFixture.TargetAssetPath, "bin", "Release", tfm, AggregatedConfiguration.DefaultTestResultFolderName);
-        string diagPathPattern = Path.Combine(diagPath, @"log_.*.diag").Replace(@"\", @"\\");
+        string diagPathPattern = BuildDefaultDiagnosticFilePathPattern(diagPath, tfm);
 
         var testHost = TestInfrastructure.TestHost.LocateFrom(AssetFixture.TargetAssetPath, AssetName, tfm);
         TestHostResult testHostResult = await testHost.ExecuteAsync("--diagnostic", disableTelemetry: false, cancellationToken: TestContext.CancellationToken);
@@ -37,7 +37,7 @@ public async Task Telemetry_ByDefault_TelemetryIsEnabled(string tfm)
     public async Task Telemetry_WhenOptingOutTelemetry_WithEnvironmentVariable_TelemetryIsDisabled(string tfm)
     {
         string diagPath = Path.Combine(AssetFixture.TargetAssetPath, "bin", "Release", tfm, AggregatedConfiguration.DefaultTestResultFolderName);
-        string diagPathPattern = Path.Combine(diagPath, @"log_.*.diag").Replace(@"\", @"\\");
+        string diagPathPattern = BuildDefaultDiagnosticFilePathPattern(diagPath, tfm);
 
         var testHost = TestInfrastructure.TestHost.LocateFrom(AssetFixture.TargetAssetPath, AssetName, tfm);
         TestHostResult testHostResult = await testHost.ExecuteAsync(
@@ -66,7 +66,7 @@ public async Task Telemetry_WhenOptingOutTelemetry_WithEnvironmentVariable_Telem
     public async Task Telemetry_WhenOptingOutTelemetry_With_DOTNET_CLI_EnvironmentVariable_TelemetryIsDisabled(string tfm)
     {
         string diagPath = Path.Combine(AssetFixture.TargetAssetPath, "bin", "Release", tfm, AggregatedConfiguration.DefaultTestResultFolderName);
-        string diagPathPattern = Path.Combine(diagPath, @"log_.*.diag").Replace(@"\", @"\\");
+        string diagPathPattern = BuildDefaultDiagnosticFilePathPattern(diagPath, tfm);
 
         var testHost = TestInfrastructure.TestHost.LocateFrom(AssetFixture.TargetAssetPath, AssetName, tfm);
         TestHostResult testHostResult = await testHost.ExecuteAsync(
@@ -113,6 +113,17 @@ private static async Task<string> AssertDiagnosticReportAsync(TestHostResult tes
         return (Regex.IsMatch(content, pattern), content);
     }
 
+    // Build a regex matching the deterministic default diagnostic file name shape:
+    // "<asset-name>_<tfm>_<arch>_<yyMMddHHmmssfff>.diag". The arch token is taken from the
+    // current process (the testhost runs on the same machine, so its ProcessArchitecture matches).
+    private static string BuildDefaultDiagnosticFilePathPattern(string diagPath, string tfm)
+    {
+        string arch = RuntimeInformation.ProcessArchitecture.ToString().ToLowerInvariant();
+        const string FileNamePlaceholder = "__DIAG_FILENAME__";
+        string combinedPath = Path.Combine(diagPath, FileNamePlaceholder).Replace(@"\", @"\\");
+        return combinedPath.Replace(FileNamePlaceholder, $@"{AssetName}_{Regex.Escape(tfm)}_{arch}_\d{{15}}\.diag");
+    }
+
     public sealed class TestAssetFixture() : TestAssetFixtureBase()
     {
         private const string WithTelemetry = nameof(WithTelemetry);