diff --git a/oak-core/pom.xml b/oak-core/pom.xml
index ee58381..0136378 100644
--- a/oak-core/pom.xml
+++ b/oak-core/pom.xml
@@ -281,11 +281,5 @@
       <version>1.1.1</version>
       <scope>test</scope>
     </dependency>
-    <dependency>
-      <groupId>org.assertj</groupId>
-      <artifactId>assertj-core</artifactId>
-      <version>3.6.2</version>
-      <scope>test</scope>
-    </dependency>
   </dependencies>
 </project>
diff --git a/oak-core/src/test/java/org/apache/jackrabbit/oak/query/stats/QuerySimilarCostTest.java b/oak-core/src/test/java/org/apache/jackrabbit/oak/query/stats/QuerySimilarCostTest.java
index c1f5a5d..c3fbcdc 100644
--- a/oak-core/src/test/java/org/apache/jackrabbit/oak/query/stats/QuerySimilarCostTest.java
+++ b/oak-core/src/test/java/org/apache/jackrabbit/oak/query/stats/QuerySimilarCostTest.java
@@ -23,6 +23,7 @@ import org.apache.jackrabbit.JcrConstants;
 import org.apache.jackrabbit.oak.InitialContent;
 import org.apache.jackrabbit.oak.Oak;
 import org.apache.jackrabbit.oak.api.ContentRepository;
+import org.apache.jackrabbit.oak.commons.junit.LogCustomizer;
 import org.apache.jackrabbit.oak.plugins.index.property.PropertyIndexEditorProvider;
 import org.apache.jackrabbit.oak.plugins.index.property.PropertyIndexPlan;
 import org.apache.jackrabbit.oak.plugins.index.property.PropertyIndexProvider;
@@ -39,18 +40,12 @@ import org.apache.jackrabbit.oak.spi.query.QueryIndexProvider;
 import org.apache.jackrabbit.oak.spi.security.OpenSecurityProvider;
 import org.apache.jackrabbit.oak.spi.state.NodeState;
 import org.apache.jackrabbit.oak.util.NodeUtil;
-import org.assertj.core.api.Assertions;
-import org.assertj.core.groups.Tuple;
 import org.jetbrains.annotations.NotNull;
+import org.junit.Assert;
 import org.junit.Test;
-import org.slf4j.LoggerFactory;
 
 import com.google.common.collect.ImmutableList;
-
-import ch.qos.logback.classic.Level;
-import ch.qos.logback.classic.Logger;
-import ch.qos.logback.classic.spi.ILoggingEvent;
-import ch.qos.logback.core.read.ListAppender;
+import org.slf4j.event.Level;
 
 /**
  * Tests for cases where two or more indices return a similar cost estimation for the same query
@@ -77,14 +72,12 @@ public class QuerySimilarCostTest extends AbstractQueryTest {
      */
     @Test
     public void testSimilarCostIndices() throws Exception{
-        Logger queryImplLogger = (Logger) LoggerFactory.getLogger(QueryImpl.class);
-        queryImplLogger.setLevel(ch.qos.logback.classic.Level.DEBUG);
-
-        ListAppender<ILoggingEvent> listAppender = new ListAppender<>();
-        listAppender.start();
+        LogCustomizer logCustomizer = LogCustomizer.forLogger(QueryImpl.class.getName()).enable(Level.DEBUG).contains("check query explanation").create();
 
         try {
-            queryImplLogger.addAppender(listAppender);
+
+            logCustomizer.starting();
+
             NodeUtil node = new NodeUtil(root.getTree("/"));
             String uuid = UUID.randomUUID().toString();
             node.setString(JcrConstants.JCR_UUID, uuid);
@@ -96,13 +89,14 @@ public class QuerySimilarCostTest extends AbstractQueryTest {
                     "with plan testIndexPlan1 and %s with plan testIndexPlan2 have similar costs 11.0 and 11.0 " +
                     "for query Filter(query=SELECT * FROM [nt:base] WHERE [jcr:uuid] is not null, path=*, property=[jcr:uuid=[is not null]]) - check query explanation / index definitions",testIndexProvider.index,testIndexProvider.index);
 
-            listAppender.stop();
-            Assertions.assertThat(listAppender.list)
-                    .extracting(ILoggingEvent::getMessage, ILoggingEvent::getLevel)
-                    .contains(Tuple.tuple(expectedLogMessage, Level.DEBUG));
+            boolean check = false;
+            for(String msg : logCustomizer.getLogs()) {
+                check = msg.equals(expectedLogMessage);
+                if (check) break;
             }
-        finally {
-            listAppender.stop();
+            Assert.assertTrue("Debug Log stating similar costs for indexes not found",check);
+        }finally {
+            logCustomizer.finished();
         }
     }