diff --git a/core/src/main/java/org/apache/calcite/sql2rel/SqlToRelConverter.java b/core/src/main/java/org/apache/calcite/sql2rel/SqlToRelConverter.java
index 977a986cf40..f0dc70c0f1c 100644
--- a/core/src/main/java/org/apache/calcite/sql2rel/SqlToRelConverter.java
+++ b/core/src/main/java/org/apache/calcite/sql2rel/SqlToRelConverter.java
@@ -3402,9 +3402,6 @@ protected final void createAggImpl(
     for (SqlNode e : r.groupExprList) {
       aggConverter.addGroupExpr(e);
     }
-    for (SqlNode e : r.measureExprList) {
-      aggConverter.addMeasureExpr(e);
-    }
 
     final RexNode havingExpr;
     final PairList<RexNode, String> projects = PairList.of();
diff --git a/core/src/test/java/org/apache/calcite/test/SqlToRelConverterTest.java b/core/src/test/java/org/apache/calcite/test/SqlToRelConverterTest.java
index 2e7efba9fdf..a38ebf0b3be 100644
--- a/core/src/test/java/org/apache/calcite/test/SqlToRelConverterTest.java
+++ b/core/src/test/java/org/apache/calcite/test/SqlToRelConverterTest.java
@@ -4690,6 +4690,23 @@ void checkUserDefinedOrderByOver(NullCollation nullCollation) {
         .ok();
   }
 
+  /** Test case for:
+   * <a href="https://issues.apache.org/jira/browse/CALCITE-6013">[CALCITE-6013]
+   * Unnecessary measures added as projects during rel construction</a>.
+   */
+  @Test void testAvoidUnnecessaryMeasureProject() {
+    final String sql = "select deptno\n"
+        + "from empm\n"
+        + "group by deptno";
+    fixture()
+        .withFactory(c ->
+            c.withOperatorTable(t ->
+                SqlValidatorTest.operatorTableFor(SqlLibrary.CALCITE)))
+        .withCatalogReader(MockCatalogReaderExtended::create)
+        .withSql(sql)
+        .ok();
+  }
+
   /** Test case for:
    * <a href="https://issues.apache.org/jira/browse/CALCITE-3310">[CALCITE-3310]
    * Approximate and exact aggregate calls are recognized as the same
diff --git a/core/src/test/resources/org/apache/calcite/test/SqlToRelConverterTest.xml b/core/src/test/resources/org/apache/calcite/test/SqlToRelConverterTest.xml
index 1085b724fa2..b914e14dc74 100644
--- a/core/src/test/resources/org/apache/calcite/test/SqlToRelConverterTest.xml
+++ b/core/src/test/resources/org/apache/calcite/test/SqlToRelConverterTest.xml
@@ -521,6 +521,20 @@ LogicalProject(EXPR$0=[ROW(ITEM(ITEM(ITEM(ITEM($3, 0), 'detail'), 'skills'), 0).
       <![CDATA[
 LogicalProject(EXPR$0=[ITEM(ITEM($3, 1).DETAIL.SKILLS, +(2, 3)).DESC])
   LogicalTableScan(table=[[CATALOG, SALES, DEPT_NESTED]])
+]]>
+    </Resource>
+  </TestCase>
+  <TestCase name="testAvoidUnnecessaryMeasureProject">
+    <Resource name="sql">
+      <![CDATA[select deptno
+from empm
+group by deptno]]>
+    </Resource>
+    <Resource name="plan">
+      <![CDATA[
+LogicalAggregate(group=[{0}])
+  LogicalProject(DEPTNO=[$7])
+    LogicalTableScan(table=[[CATALOG, SALES, EMPM]])
 ]]>
     </Resource>
   </TestCase>
@@ -4502,7 +4516,7 @@ group by deptno]]>
     <Resource name="plan">
       <![CDATA[
 LogicalAggregate(group=[{0}], C=[AGGREGATE($1)])
-  LogicalProject(DEPTNO=[$7], COUNT_PLUS_100=[$9], COUNT_TIMES_100=[$10])
+  LogicalProject(DEPTNO=[$7], COUNT_PLUS_100=[$9])
     LogicalTableScan(table=[[CATALOG, SALES, EMPM]])
 ]]>
     </Resource>