diff --git a/src/libraries/Microsoft.Extensions.FileProviders.Physical/tests/PhysicalFileProviderTests.cs b/src/libraries/Microsoft.Extensions.FileProviders.Physical/tests/PhysicalFileProviderTests.cs
index d972b3626e1bdd..e0667e1093b974 100644
--- a/src/libraries/Microsoft.Extensions.FileProviders.Physical/tests/PhysicalFileProviderTests.cs
+++ b/src/libraries/Microsoft.Extensions.FileProviders.Physical/tests/PhysicalFileProviderTests.cs
@@ -1270,6 +1270,13 @@ void Fail(object state)
             using (var physicalFilesWatcher = new PhysicalFilesWatcher(root.Path + Path.DirectorySeparatorChar, fileSystemWatcher, pollForChanges: false))
             using (var provider = new PhysicalFileProvider(root.Path) { FileWatcher = physicalFilesWatcher })
             {
+                // This test only relies on the watcher events that are injected below via
+                // fileSystemWatcher.CallOnRenamed, which invokes FileSystemWatcher.OnRenamed directly and
+                // so bypasses Filter matching. Setting a Filter that cannot match any of the (randomly
+                // generated) names used by this test suppresses any genuine native events - e.g. ones
+                // belatedly reported by macOS fseventsd for the directory/file creation below.
+                fileSystemWatcher.Filter = "this-filter-does-not-match-anything";
+
                 var oldDirectoryName = Guid.NewGuid().ToString();
                 var oldSubDirectoryName = Guid.NewGuid().ToString();
                 var oldSubDirectoryPath = Path.Combine(oldDirectoryName, oldSubDirectoryName);