diff --git a/src/com/google/javascript/jscomp/parsing/IRFactory.java b/src/com/google/javascript/jscomp/parsing/IRFactory.java
index c7adc62ab27..c55eccea433 100644
--- a/src/com/google/javascript/jscomp/parsing/IRFactory.java
+++ b/src/com/google/javascript/jscomp/parsing/IRFactory.java
@@ -1436,11 +1436,11 @@ Node processIfStatement(IfStatementTree statementNode) {
     }
 
     Node processBinaryExpression(BinaryOperatorTree exprNode) {
-      if (exprNode.operator.type == TokenType.STAR_STAR
-          || exprNode.operator.type == TokenType.STAR_STAR_EQUAL) {
-        maybeWarnForFeature(exprNode, Feature.EXPONENT_OP);
-      }
       if (hasPendingCommentBefore(exprNode.right)) {
+        if (exprNode.operator.type == TokenType.STAR_STAR
+            || exprNode.operator.type == TokenType.STAR_STAR_EQUAL) {
+          maybeWarnForFeature(exprNode, Feature.EXPONENT_OP);
+        }
         return newNode(
             transformBinaryTokenType(exprNode.operator.type),
             transform(exprNode.left),
@@ -1458,6 +1458,10 @@ private Node processBinaryExpressionHelper(BinaryOperatorTree exprTree) {
       Node current = null;
       Node previous = null;
       while (exprTree != null) {
+        if (exprTree.operator.type == TokenType.STAR_STAR
+            || exprTree.operator.type == TokenType.STAR_STAR_EQUAL) {
+          maybeWarnForFeature(exprTree, Feature.EXPONENT_OP);
+        }
         previous = current;
         // Skip the first child but recurse normally into the right operand as typically this isn't
         // deep and because we have already checked that there isn't any JSDoc we can traverse
diff --git a/test/com/google/javascript/jscomp/Es7ToEs6ConverterTest.java b/test/com/google/javascript/jscomp/Es7ToEs6ConverterTest.java
index 03e1e683573..68e045263cc 100644
--- a/test/com/google/javascript/jscomp/Es7ToEs6ConverterTest.java
+++ b/test/com/google/javascript/jscomp/Es7ToEs6ConverterTest.java
@@ -53,4 +53,8 @@ public void testExponentiationOperator() {
   public void testExponentiationAssignmentOperator() {
     test("x **= 2;", "x=Math.pow(x,2)");
   }
+
+  public void testIssue2821() {
+    test("2 ** 3 > 0", "Math.pow(2, 3) > 0");
+  }
 }
diff --git a/test/com/google/javascript/jscomp/parsing/ParserTest.java b/test/com/google/javascript/jscomp/parsing/ParserTest.java
index f6f8db41506..f63d9c6ed81 100644
--- a/test/com/google/javascript/jscomp/parsing/ParserTest.java
+++ b/test/com/google/javascript/jscomp/parsing/ParserTest.java
@@ -102,6 +102,8 @@ public void testExponentOperator() {
     parse("x**-y");
     parse("x/y**z");
 
+    parse("2 ** 3 > 3");
+
     mode = LanguageMode.ECMASCRIPT6;
     strictMode = SLOPPY;
     parseWarning(