diff --git a/src/ORM/PolymorphicHasManyList.php b/src/ORM/PolymorphicHasManyList.php
index 261209f65..6f1908441 100644
--- a/src/ORM/PolymorphicHasManyList.php
+++ b/src/ORM/PolymorphicHasManyList.php
@@ -57,7 +57,8 @@ class PolymorphicHasManyList extends HasManyList
     public function setForeignRelation(string $relationName): static
     {
         Deprecation::notice('5.2.0', 'Will be replaced with a parameter in the constructor');
-        $this->dataQuery->where(["\"{$this->relationForeignKey}\"" => $relationName]);
+        $foreignRelationColumn = DataObject::getSchema()->sqlColumnForField($this->dataClass, $this->relationForeignKey);
+        $this->dataQuery->where([$foreignRelationColumn => $relationName]);
         $this->dataQuery->setQueryParam('Foreign.Relation', $relationName);
         return $this;
     }
@@ -102,8 +103,9 @@ class PolymorphicHasManyList extends HasManyList
         // For queries with multiple foreign IDs (such as that generated by
         // DataList::relation) the filter must be generalised to filter by subclasses
         $classNames = Convert::raw2sql(ClassInfo::subclassesFor($foreignClass));
+        $foreignClassColumn = DataObject::getSchema()->sqlColumnForField($dataClass, $this->classForeignKey);
         $this->dataQuery->where(sprintf(
-            "\"{$this->classForeignKey}\" IN ('%s')",
+            "$foreignClassColumn IN ('%s')",
             implode("', '", $classNames)
         ));
     }