diff --git a/src/legacy/ui/public/field_editor/field_editor.js b/src/legacy/ui/public/field_editor/field_editor.js
index aa9b0d61dba83..ab4f9e85d339c 100644
--- a/src/legacy/ui/public/field_editor/field_editor.js
+++ b/src/legacy/ui/public/field_editor/field_editor.js
@@ -662,7 +662,7 @@ export class FieldEditorComponent extends PureComponent {
     }
 
     if (!fieldFormatId) {
-      indexPattern.fieldFormatMap[field.name] = {};
+      indexPattern.fieldFormatMap[field.name] = undefined;
     } else {
       indexPattern.fieldFormatMap[field.name] = field.format;
     }
diff --git a/test/functional/apps/management/_scripted_fields.js b/test/functional/apps/management/_scripted_fields.js
index a3077e965dd4c..3e901388ed383 100644
--- a/test/functional/apps/management/_scripted_fields.js
+++ b/test/functional/apps/management/_scripted_fields.js
@@ -73,6 +73,33 @@ export default function ({ getService, getPageObjects }) {
       });
     });
 
+
+    describe('testing regression for issue #33251', function describeIndexTests() {
+      const scriptedPainlessFieldName = 'ram_Pain_reg';
+
+      it('should create and edit scripted field', async function () {
+        await PageObjects.settings.navigateTo();
+        await PageObjects.settings.clickKibanaIndexPatterns();
+        await PageObjects.settings.clickIndexPatternLogstash();
+        const startingCount = parseInt(await PageObjects.settings.getScriptedFieldsTabCount());
+        await PageObjects.settings.clickScriptedFieldsTab();
+        await log.debug('add scripted field');
+        const script = `1`;
+        await PageObjects.settings.addScriptedField(scriptedPainlessFieldName, 'painless', 'number', null, '1', script);
+        await retry.try(async function () {
+          expect(parseInt(await PageObjects.settings.getScriptedFieldsTabCount())).to.be(startingCount + 1);
+        });
+
+        for (let i = 0; i < 3; i++) {
+          await PageObjects.settings.editScriptedField(scriptedPainlessFieldName);
+          const fieldSaveButton = await testSubjects.exists('fieldSaveButton');
+          expect(fieldSaveButton).to.be(true);
+          await PageObjects.settings.clickSaveScriptedField();
+        }
+      });
+    });
+
+
     describe('creating and using Painless numeric scripted fields', function describeIndexTests() {
       const scriptedPainlessFieldName = 'ram_Pain1';
 
diff --git a/test/functional/page_objects/settings_page.js b/test/functional/page_objects/settings_page.js
index 2e728db3b388d..2b42906717f36 100644
--- a/test/functional/page_objects/settings_page.js
+++ b/test/functional/page_objects/settings_page.js
@@ -380,6 +380,11 @@ export function SettingsPageProvider({ getService, getPageObjects }) {
       await testSubjects.click('tab-sourceFilters');
     }
 
+    async editScriptedField(name) {
+      await this.filterField(name);
+      await find.clickByCssSelector('.euiTableRowCell--hasActions button:first-child');
+    }
+
     async addScriptedField(name, language, type, format, popularity, script) {
       await this.clickAddScriptedField();
       await this.setScriptedFieldName(name);