diff --git a/rules-tests/CodeQuality/Rector/If_/CombineIfRector/Fixture/with_assign.php.inc b/rules-tests/CodeQuality/Rector/If_/CombineIfRector/Fixture/with_assign.php.inc
new file mode 100644
index 00000000000..b9733cb238c
--- /dev/null
+++ b/rules-tests/CodeQuality/Rector/If_/CombineIfRector/Fixture/with_assign.php.inc
@@ -0,0 +1,33 @@
+<?php
+
+namespace Rector\Tests\CodeQuality\Rector\If_\CombineIfRector\Fixture;
+
+final class WithAssign
+{
+    public function run()
+    {
+        if ($cond1) {
+            if (($cond2 = $this->getCond2Value()) === null) {
+                return 'foo';
+            }
+        }
+    }
+}
+
+?>
+-----
+<?php
+
+namespace Rector\Tests\CodeQuality\Rector\If_\CombineIfRector\Fixture;
+
+final class WithAssign
+{
+    public function run()
+    {
+        if ($cond1 && ($cond2 = $this->getCond2Value()) === null) {
+            return 'foo';
+        }
+    }
+}
+
+?>
diff --git a/rules/CodeQuality/Rector/If_/CombineIfRector.php b/rules/CodeQuality/Rector/If_/CombineIfRector.php
index a25ba8dfc01..17c81ccb391 100644
--- a/rules/CodeQuality/Rector/If_/CombineIfRector.php
+++ b/rules/CodeQuality/Rector/If_/CombineIfRector.php
@@ -98,6 +98,10 @@ public function refactor(Node $node): ?Node
             $cond = $cond->right;
         }
 
+        if ($subIf->cond instanceof BinaryOp && ! $subIf->cond->left instanceof BinaryOp) {
+            $subIf->cond->left->setAttribute(AttributeKey::ORIGINAL_NODE, null);
+        }
+
         $node->cond = new BooleanAnd($node->cond, $subIf->cond);
 
         $node->stmts = $subIf->stmts;