diff --git a/core/src/test/java/google/registry/testing/AppEngineExtension.java b/core/src/test/java/google/registry/testing/AppEngineExtension.java
index aceeb0400..b86d16405 100644
--- a/core/src/test/java/google/registry/testing/AppEngineExtension.java
+++ b/core/src/test/java/google/registry/testing/AppEngineExtension.java
@@ -487,20 +487,22 @@ public final class AppEngineExtension implements BeforeEachCallback, AfterEachCa
       if (replayer != null) {
         replayer.replay();
       }
-
-      if (withCloudSql) {
-        if (enableJpaEntityCoverageCheck) {
-          jpaIntegrationWithCoverageExtension.afterEach(context);
-        } else if (withJpaUnitTest) {
-          jpaUnitTestExtension.afterEach(context);
-        } else {
-          jpaIntegrationTestExtension.afterEach(context);
-        }
-      }
-      tearDown();
     } finally {
-      if (isWithDatastoreAndCloudSql()) {
-        restoreTmAfterDualDatabaseTest(context);
+      try {
+        if (withCloudSql) {
+          if (enableJpaEntityCoverageCheck) {
+            jpaIntegrationWithCoverageExtension.afterEach(context);
+          } else if (withJpaUnitTest) {
+            jpaUnitTestExtension.afterEach(context);
+          } else {
+            jpaIntegrationTestExtension.afterEach(context);
+          }
+        }
+        tearDown();
+      } finally {
+        if (isWithDatastoreAndCloudSql()) {
+          restoreTmAfterDualDatabaseTest(context);
+        }
       }
     }
   }
diff --git a/core/src/test/java/google/registry/testing/TestLogHandlerUtils.java b/core/src/test/java/google/registry/testing/TestLogHandlerUtils.java
index 9e541b6b2..fc384cac1 100644
--- a/core/src/test/java/google/registry/testing/TestLogHandlerUtils.java
+++ b/core/src/test/java/google/registry/testing/TestLogHandlerUtils.java
@@ -43,6 +43,15 @@ public final class TestLogHandlerUtils {
         handler.getStoredLogRecords(), logRecord -> logRecord.getMessage().startsWith(prefix));
   }
 
+  /** Assert that the specified log message is <em>not</em> found. */
+  public static void assertNoLogMessage(CapturingLogHandler handler, Level level, String message) {
+    for (LogRecord logRecord : handler.getRecords()) {
+      if (logRecord.getLevel().equals(level) && logRecord.getMessage().contains(message)) {
+        assertWithMessage("Log message \"%s\" found: %s", message, logRecord.getMessage()).fail();
+      }
+    }
+  }
+
   public static void assertLogMessage(CapturingLogHandler handler, Level level, String message) {
     for (LogRecord logRecord : handler.getRecords()) {
       if (logRecord.getLevel().equals(level) && logRecord.getMessage().contains(message)) {
diff --git a/core/src/test/java/google/registry/tools/CommandTestCase.java b/core/src/test/java/google/registry/tools/CommandTestCase.java
index 556af5f60..5f404119f 100644
--- a/core/src/test/java/google/registry/tools/CommandTestCase.java
+++ b/core/src/test/java/google/registry/tools/CommandTestCase.java
@@ -42,7 +42,6 @@ import java.io.OutputStream;
 import java.io.PrintStream;
 import java.nio.file.Path;
 import java.util.List;
-import java.util.concurrent.locks.ReentrantLock;
 import org.joda.time.DateTime;
 import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.BeforeEach;
@@ -59,10 +58,6 @@ import org.mockito.junit.jupiter.MockitoExtension;
 @ExtendWith(MockitoExtension.class)
 public abstract class CommandTestCase<C extends Command> {
 
-  // Lock for stdout/stderr.  Note that this is static: since we're dealing with globals, we need
-  // to lock for the entire JVM.
-  private static final ReentrantLock streamsLock = new ReentrantLock();
-
   private final ByteArrayOutputStream stdout = new ByteArrayOutputStream();
   private final ByteArrayOutputStream stderr = new ByteArrayOutputStream();
   private PrintStream oldStdout, oldStderr;
@@ -90,10 +85,7 @@ public abstract class CommandTestCase<C extends Command> {
     RegistryToolEnvironment.UNITTEST.setup(systemPropertyExtension);
     command = newCommandInstance();
 
-    // Capture standard output/error. This is problematic because gradle tests run in parallel in
-    // the same JVM.  So first lock out any other tests in this JVM that are trying to do this
-    // trick.
-    streamsLock.lock();
+    // Capture standard output/error.
     oldStdout = System.out;
     System.setOut(new PrintStream(new OutputSplitter(System.out, stdout)));
     oldStderr = System.err;
@@ -104,7 +96,6 @@ public abstract class CommandTestCase<C extends Command> {
   public final void afterEachCommandTestCase() {
     System.setOut(oldStdout);
     System.setErr(oldStderr);
-    streamsLock.unlock();
   }
 
   void runCommandInEnvironment(RegistryToolEnvironment env, String... args) throws Exception {
diff --git a/core/src/test/java/google/registry/tools/UpdateDomainCommandTest.java b/core/src/test/java/google/registry/tools/UpdateDomainCommandTest.java
index a8ed424c3..6d1be6d6a 100644
--- a/core/src/test/java/google/registry/tools/UpdateDomainCommandTest.java
+++ b/core/src/test/java/google/registry/tools/UpdateDomainCommandTest.java
@@ -25,12 +25,15 @@ import static google.registry.testing.DatabaseHelper.newDomainBase;
 import static google.registry.testing.DatabaseHelper.persistActiveDomain;
 import static google.registry.testing.DatabaseHelper.persistActiveHost;
 import static google.registry.testing.DatabaseHelper.persistResource;
+import static google.registry.testing.TestLogHandlerUtils.assertLogMessage;
+import static google.registry.testing.TestLogHandlerUtils.assertNoLogMessage;
 import static google.registry.util.DateTimeUtils.END_OF_TIME;
 import static org.junit.jupiter.api.Assertions.assertThrows;
 
 import com.beust.jcommander.ParameterException;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.ImmutableSet;
+import com.google.common.flogger.LoggerConfig;
 import google.registry.model.billing.BillingEvent;
 import google.registry.model.billing.BillingEvent.Flag;
 import google.registry.model.billing.BillingEvent.Reason;
@@ -46,6 +49,9 @@ import google.registry.persistence.VKey;
 import google.registry.testing.DualDatabaseTest;
 import google.registry.testing.InjectExtension;
 import google.registry.testing.TestOfyAndSql;
+import google.registry.util.CapturingLogHandler;
+import java.util.logging.Level;
+import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.extension.RegisterExtension;
 
@@ -53,6 +59,8 @@ import org.junit.jupiter.api.extension.RegisterExtension;
 @DualDatabaseTest
 class UpdateDomainCommandTest extends EppToolCommandTestCase<UpdateDomainCommand> {
 
+  private final CapturingLogHandler logHandler = new CapturingLogHandler();
+
   private DomainBase domain;
 
   @RegisterExtension public final InjectExtension inject = new InjectExtension();
@@ -62,6 +70,12 @@ class UpdateDomainCommandTest extends EppToolCommandTestCase<UpdateDomainCommand
     inject.setStaticField(Ofy.class, "clock", fakeClock);
     command.clock = fakeClock;
     domain = persistActiveDomain("example.tld");
+    LoggerConfig.getConfig(UpdateDomainCommand.class).addHandler(logHandler);
+  }
+
+  @AfterEach
+  void afterEach() {
+    LoggerConfig.getConfig(UpdateDomainCommand.class).removeHandler(logHandler);
   }
 
   @TestOfyAndSql
@@ -299,7 +313,7 @@ class UpdateDomainCommandTest extends EppToolCommandTestCase<UpdateDomainCommand
     runCommandForced("--client=NewRegistrar", "--autorenews=false", "example.tld");
     eppVerifier.verifySent(
         "domain_update_set_autorenew.xml", ImmutableMap.of("AUTORENEWS", "false"));
-    assertThat(getStderrAsString()).doesNotContain("autorenew grace period");
+    assertNoLogMessage(logHandler, Level.WARNING, "autorenew grace period");
   }
 
   @TestOfyAndSql
@@ -340,9 +354,9 @@ class UpdateDomainCommandTest extends EppToolCommandTestCase<UpdateDomainCommand
     runCommandForced("--client=NewRegistrar", "--autorenews=false", "example.tld");
     eppVerifier.verifySent(
         "domain_update_set_autorenew.xml", ImmutableMap.of("AUTORENEWS", "false"));
-    String stdErr = getStderrAsString();
-    assertThat(stdErr).contains("The following domains are in autorenew grace periods.");
-    assertThat(stdErr).contains("example.tld");
+    assertLogMessage(
+        logHandler, Level.WARNING, "The following domains are in autorenew grace periods.");
+    assertLogMessage(logHandler, Level.WARNING, "example.tld");
   }
 
   @TestOfyAndSql