diff --git a/phoenix-core/src/main/java/org/apache/phoenix/query/ConnectionQueryServicesImpl.java b/phoenix-core/src/main/java/org/apache/phoenix/query/ConnectionQueryServicesImpl.java
index 92794dc54d5..d0bd6ed21e8 100644
--- a/phoenix-core/src/main/java/org/apache/phoenix/query/ConnectionQueryServicesImpl.java
+++ b/phoenix-core/src/main/java/org/apache/phoenix/query/ConnectionQueryServicesImpl.java
@@ -4359,19 +4359,12 @@ void ensureSystemTablesMigratedToSystemNamespace()
      * making use of HBase's checkAndPut api.
      *
      * @return true if client won the race, false otherwise
-     * @throws IOException
      * @throws SQLException
      */
     @VisibleForTesting
     public boolean acquireUpgradeMutex(long currentServerSideTableTimestamp)
-            throws IOException,
-            SQLException {
+            throws SQLException {
         Preconditions.checkArgument(currentServerSideTableTimestamp < MIN_SYSTEM_TABLE_TIMESTAMP);
-        byte[] sysMutexPhysicalTableNameBytes = getSysMutexPhysicalTableNameBytes();
-        if(sysMutexPhysicalTableNameBytes == null) {
-            throw new UpgradeInProgressException(getVersion(currentServerSideTableTimestamp),
-                    getVersion(MIN_SYSTEM_TABLE_TIMESTAMP));
-        }
         if (!writeMutexCell(null, PhoenixDatabaseMetaData.SYSTEM_CATALOG_SCHEMA,
             PhoenixDatabaseMetaData.SYSTEM_CATALOG_TABLE, null, null)) {
             throw new UpgradeInProgressException(getVersion(currentServerSideTableTimestamp),
@@ -4384,15 +4377,13 @@ public boolean acquireUpgradeMutex(long currentServerSideTableTimestamp)
     public boolean writeMutexCell(String tenantId, String schemaName, String tableName,
             String columnName, String familyName) throws SQLException {
         try {
-            byte[] rowKey =
-                    columnName != null
-                            ? SchemaUtil.getColumnKey(tenantId, schemaName, tableName, columnName,
-                                familyName)
-                            : SchemaUtil.getTableKey(tenantId, schemaName, tableName);
+            byte[] rowKey = columnName != null
+                ? SchemaUtil.getColumnKey(tenantId, schemaName, tableName,
+                    columnName, familyName)
+                : SchemaUtil.getTableKey(tenantId, schemaName, tableName);
             // at this point the system mutex table should have been created or
             // an exception thrown
-            byte[] sysMutexPhysicalTableNameBytes = getSysMutexPhysicalTableNameBytes();
-            try (Table sysMutexTable = getTable(sysMutexPhysicalTableNameBytes)) {
+            try (Table sysMutexTable = getSysMutexTable()) {
                 byte[] family = PhoenixDatabaseMetaData.SYSTEM_MUTEX_FAMILY_NAME_BYTES;
                 byte[] qualifier = PhoenixDatabaseMetaData.SYSTEM_MUTEX_COLUMN_NAME_BYTES;
                 byte[] value = MUTEX_LOCKED;
@@ -4428,15 +4419,13 @@ public void releaseUpgradeMutex() throws IOException, SQLException {
     public void deleteMutexCell(String tenantId, String schemaName, String tableName,
             String columnName, String familyName) throws SQLException {
         try {
-            byte[] rowKey =
-                    columnName != null
-                            ? SchemaUtil.getColumnKey(tenantId, schemaName, tableName, columnName,
-                                familyName)
-                            : SchemaUtil.getTableKey(tenantId, schemaName, tableName);
+            byte[] rowKey = columnName != null
+                ? SchemaUtil.getColumnKey(tenantId, schemaName, tableName,
+                    columnName, familyName)
+                : SchemaUtil.getTableKey(tenantId, schemaName, tableName);
             // at this point the system mutex table should have been created or
             // an exception thrown
-            byte[] sysMutexPhysicalTableNameBytes = getSysMutexPhysicalTableNameBytes();
-            try (Table sysMutexTable = getTable(sysMutexPhysicalTableNameBytes)) {
+            try (Table sysMutexTable = getSysMutexTable()) {
                 byte[] family = PhoenixDatabaseMetaData.SYSTEM_MUTEX_FAMILY_NAME_BYTES;
                 byte[] qualifier = PhoenixDatabaseMetaData.SYSTEM_MUTEX_COLUMN_NAME_BYTES;
                 Delete delete = new Delete(rowKey);
@@ -4454,17 +4443,18 @@ public void deleteMutexCell(String tenantId, String schemaName, String tableName
         }
     }
 
-    private byte[] getSysMutexPhysicalTableNameBytes() throws IOException, SQLException {
-        byte[] sysMutexPhysicalTableNameBytes = null;
-        try(Admin admin = getAdmin()) {
-            if(admin.tableExists(PhoenixDatabaseMetaData.SYSTEM_MUTEX_HBASE_TABLE_NAME)) {
-                sysMutexPhysicalTableNameBytes = PhoenixDatabaseMetaData.SYSTEM_MUTEX_NAME_BYTES;
-            } else if (admin.tableExists(TableName.valueOf(
-                    SchemaUtil.getPhysicalTableName(SYSTEM_MUTEX_NAME, props).getName()))) {
-                sysMutexPhysicalTableNameBytes = SchemaUtil.getPhysicalTableName(SYSTEM_MUTEX_NAME, props).getName();
+    @VisibleForTesting
+    public Table getSysMutexTable() throws SQLException, IOException {
+        String table = SYSTEM_MUTEX_NAME;
+        TableName tableName = TableName.valueOf(table);
+        try (Admin admin = getAdmin()) {
+            if (!admin.tableExists(tableName)) {
+                table = table.replace(QueryConstants.NAME_SEPARATOR,
+                    QueryConstants.NAMESPACE_SEPARATOR);
+                tableName = TableName.valueOf(table);
             }
+            return connection.getTable(tableName);
         }
-        return sysMutexPhysicalTableNameBytes;
     }
 
     private String addColumn(String columnsToAddSoFar, String columns) {
diff --git a/phoenix-core/src/test/java/org/apache/phoenix/query/ConnectionQueryServicesImplTest.java b/phoenix-core/src/test/java/org/apache/phoenix/query/ConnectionQueryServicesImplTest.java
index 08e7f91c8ed..205267696bd 100644
--- a/phoenix-core/src/test/java/org/apache/phoenix/query/ConnectionQueryServicesImplTest.java
+++ b/phoenix-core/src/test/java/org/apache/phoenix/query/ConnectionQueryServicesImplTest.java
@@ -23,6 +23,7 @@
 import static org.apache.phoenix.jdbc.PhoenixDatabaseMetaData.TTL_FOR_MUTEX;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertSame;
 import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
 import static org.mockito.Matchers.any;
@@ -46,7 +47,9 @@
 import org.apache.hadoop.hbase.client.Admin;
 import org.apache.hadoop.hbase.TableNotFoundException;
 import org.apache.hadoop.hbase.client.ColumnFamilyDescriptorBuilder;
+import org.apache.hadoop.hbase.client.Connection;
 import org.apache.hadoop.hbase.client.Mutation;
+import org.apache.hadoop.hbase.client.Table;
 import org.apache.hadoop.hbase.client.TableDescriptor;
 import org.apache.hadoop.hbase.client.TableDescriptorBuilder;
 import org.apache.phoenix.exception.PhoenixIOException;
@@ -78,6 +81,12 @@ public class ConnectionQueryServicesImplTest {
     @Mock
     private ReadOnlyProps readOnlyProps;
 
+    @Mock
+    private Connection mockConn;
+
+    @Mock
+    private Table mockTable;
+
     public static final TableDescriptorBuilder SYS_TASK_TDB = TableDescriptorBuilder
         .newBuilder(TableName.valueOf(PhoenixDatabaseMetaData.SYSTEM_TASK_NAME));
     public static final TableDescriptorBuilder SYS_TASK_TDB_SP = TableDescriptorBuilder
@@ -93,12 +102,17 @@ public void setup() throws IOException, NoSuchFieldException,
             .getDeclaredField("props");
         props.setAccessible(true);
         props.set(mockCqs, readOnlyProps);
+        props = ConnectionQueryServicesImpl.class.getDeclaredField("connection");
+        props.setAccessible(true);
+        props.set(mockCqs, mockConn);
         when(mockCqs.checkIfSysMutexExistsAndModifyTTLIfRequired(mockAdmin))
             .thenCallRealMethod();
         when(mockCqs.updateAndConfirmSplitPolicyForTask(SYS_TASK_TDB))
             .thenCallRealMethod();
         when(mockCqs.updateAndConfirmSplitPolicyForTask(SYS_TASK_TDB_SP))
             .thenCallRealMethod();
+        when(mockCqs.getSysMutexTable()).thenCallRealMethod();
+        when(mockCqs.getAdmin()).thenCallRealMethod();
     }
 
     @SuppressWarnings("unchecked")
@@ -193,4 +207,30 @@ public void testSysTaskSplitPolicyWithError() {
                 e.getMessage());
         }
     }
+
+    @Test
+    public void testGetSysMutexTableWithName() throws Exception {
+        when(mockAdmin.tableExists(any())).thenReturn(true);
+        when(mockConn.getAdmin()).thenReturn(mockAdmin);
+        when(mockConn.getTable(TableName.valueOf("SYSTEM.MUTEX")))
+            .thenReturn(mockTable);
+        assertSame(mockCqs.getSysMutexTable(), mockTable);
+        verify(mockAdmin, Mockito.times(1)).tableExists(any());
+        verify(mockConn, Mockito.times(1)).getAdmin();
+        verify(mockConn, Mockito.times(1))
+            .getTable(TableName.valueOf("SYSTEM.MUTEX"));
+    }
+
+    @Test
+    public void testGetSysMutexTableWithNamespace() throws Exception {
+        when(mockAdmin.tableExists(any())).thenReturn(false);
+        when(mockConn.getAdmin()).thenReturn(mockAdmin);
+        when(mockConn.getTable(TableName.valueOf("SYSTEM:MUTEX")))
+          .thenReturn(mockTable);
+        assertSame(mockCqs.getSysMutexTable(), mockTable);
+        verify(mockAdmin, Mockito.times(1)).tableExists(any());
+        verify(mockConn, Mockito.times(1)).getAdmin();
+        verify(mockConn, Mockito.times(1))
+          .getTable(TableName.valueOf("SYSTEM:MUTEX"));
+    }
 }