diff --git a/src/code-stub-assembler.cc b/src/code-stub-assembler.cc
index 61df9fb75c..039090623b 100644
--- a/src/code-stub-assembler.cc
+++ b/src/code-stub-assembler.cc
@@ -10713,15 +10713,16 @@ Node* CodeStubAssembler::RelationalComparison(Operation op, Node* left,
           }
 
           // If {left} is a receiver, call ToPrimitive(left, hint Number).
-          // Otherwise call ToNumeric(left) and then ToNumeric(right).
+          // Otherwise call ToNumeric(right) and then ToNumeric(left), the
+          // order here is important as it's observable by user code.
           STATIC_ASSERT(LAST_JS_RECEIVER_TYPE == LAST_TYPE);
           Label if_left_receiver(this, Label::kDeferred);
           GotoIf(IsJSReceiverInstanceType(left_instance_type),
                  &if_left_receiver);
 
+          var_right.Bind(CallBuiltin(Builtins::kToNumeric, context, right));
           var_left.Bind(
               CallBuiltin(Builtins::kNonNumberToNumeric, context, left));
-          var_right.Bind(CallBuiltin(Builtins::kToNumeric, context, right));
           Goto(&loop);
 
           BIND(&if_left_receiver);
diff --git a/test/mjsunit/regress/regress-crbug-687063.js b/test/mjsunit/regress/regress-crbug-687063.js
new file mode 100644
index 0000000000..8c579331fb
--- /dev/null
+++ b/test/mjsunit/regress/regress-crbug-687063.js
@@ -0,0 +1,31 @@
+// Copyright 2018 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Flags: --allow-natives-syntax
+
+// Collect the actual properties looked up on the Proxy.
+const actual = [];
+
+// Perform a relational comparison with a Proxy on the right hand
+// side and a Symbol which cannot be turned into a Number on the
+// left hand side.
+function foo() {
+  actual.length = 0;
+  const lhs = Symbol();
+  const rhs = new Proxy({}, {
+    get: function(target, property, receiver) {
+      actual.push(property);
+      return undefined;
+    }
+  });
+  return lhs < rhs;
+}
+
+assertThrows(foo, TypeError);
+assertEquals([Symbol.toPrimitive, 'valueOf', 'toString'], actual);
+assertThrows(foo, TypeError);
+assertEquals([Symbol.toPrimitive, 'valueOf', 'toString'], actual);
+%OptimizeFunctionOnNextCall(foo);
+assertThrows(foo, TypeError);
+assertEquals([Symbol.toPrimitive, 'valueOf', 'toString'], actual);