diff --git a/lib/meta-box-partial-page.php b/lib/meta-box-partial-page.php
index 901aea951919bd..6a55a062ba0f8c 100644
--- a/lib/meta-box-partial-page.php
+++ b/lib/meta-box-partial-page.php
@@ -206,6 +206,9 @@ function gutenberg_intercept_meta_box_render() {
 		foreach ( $contexts as $context => $priorities ) {
 			foreach ( $priorities as $priority => $boxes ) {
 				foreach ( $boxes as $id => $box ) {
+					if ( ! is_array( $box ) ) {
+						continue;
+					}
 					if ( ! is_array( $wp_meta_boxes[ $post_type ][ $context ][ $priority ][ $id ]['args'] ) ) {
 						$wp_meta_boxes[ $post_type ][ $context ][ $priority ][ $id ]['args'] = array();
 					}
diff --git a/phpunit/class-meta-box-test.php b/phpunit/class-meta-box-test.php
index cf2c767a8bda9a..c62ef1ab1940e1 100644
--- a/phpunit/class-meta-box-test.php
+++ b/phpunit/class-meta-box-test.php
@@ -235,4 +235,18 @@ public function test_gutenberg_filter_meta_boxes_for_taxonomies() {
 
 		$this->assertEquals( $expected, $actual );
 	}
+
+	/**
+	 * Test that a removed meta box remains empty after gutenberg_intercept_meta_box_render() fires.
+	 */
+	public function test_gutenberg_intercept_meta_box_render_skips_empty_boxes() {
+		global $wp_meta_boxes;
+
+		add_meta_box( 'test-intercept-box', 'Test Intercept box', '__return_empty_string', 'post', 'side', 'default' );
+		remove_meta_box( 'test-intercept-box', 'post', 'side' );
+
+		gutenberg_intercept_meta_box_render();
+
+		$this->assertFalse( $wp_meta_boxes['post']['side']['default']['test-intercept-box'] );
+	}
 }