diff --git a/src/Duration.php b/src/Duration.php
index d0b2f32..a8015cb 100644
--- a/src/Duration.php
+++ b/src/Duration.php
@@ -188,13 +188,12 @@ final class Duration
     {
         $units += ['hour' => '0', 'minute' => '0', 'second' => '0', 'fraction' => '0', 'sign' => '+'];
         $units['fraction'] = str_pad($units['fraction'] ?? '000000', 6, '0');
-        $sign = '-' === $units['sign'] ? '-' : '';
+        if ('-' === $units['sign']) {
+            $units['hour'] = '-'.$units['hour'];
+        }
 
         return self::fromDateString(
-            $sign.$units['hour'].' hours '
-            .$sign.$units['minute'].' minutes '
-            .$sign.$units['second'].' seconds '
-            .$sign.$units['fraction'].' microseconds'
+            $units['hour'].' hours '.$units['minute'].' minutes '.$units['second'].' seconds '.$units['fraction'].' microseconds'
         );
     }
 
diff --git a/src/DurationTest.php b/src/DurationTest.php
index 12c03db..487204c 100644
--- a/src/DurationTest.php
+++ b/src/DurationTest.php
@@ -241,8 +241,8 @@ final class DurationTest extends TestCase
                 'expected' => 'PT1H2M3.0004S',
             ],
             'negative chrono' => [
-                'chronometer' => '-12:28',
-                'expected' => 'PT-12M-28S',
+                'chronometer' => '-12:28.5',
+                'expected' => 'PT12M28.5S',
             ],
         ];
     }
@@ -282,66 +282,11 @@ final class DurationTest extends TestCase
             ],
             'negative chrono' => [
                 'chronometer' => '-12:28',
-                'expected' => 'PT-12H-28M',
+                'expected' => 'PT-12H28M',
             ],
             'negative chrono with seconds' => [
-                'chronometer' => '-01:02:28',
-                'expected' => 'PT-1H-2M-28S',
-            ],
-        ];
-    }
-
-    /**
-     * A sign applies to the whole duration, not just the hour. It used to be
-     * lost when the hour was zero, and to negate only the hour otherwise.
-     */
-    #[DataProvider('signedDurationProvider')]
-    public function testSignedStringsApplySignToWholeDuration(string $method, string $input, string $reference, string $expected): void
-    {
-        $duration = Duration::$method($input);
-        $date = new \DateTimeImmutable($reference);
-
-        self::assertSame(
-            $expected,
-            $date->add($duration->dateInterval)->format('Y-m-d H:i:s.u')
-        );
-    }
-
-    /**
-     * @return iterable<string, array{method:string, input:string, reference:string, expected:string}>
-     */
-    public static function signedDurationProvider(): iterable
-    {
-        return [
-            'chrono negative minute and second without hour' => [
-                'method' => 'fromChronoString',
-                'input' => '-05:30',
-                'reference' => '2021-01-01 00:10:00.000000',
-                'expected' => '2021-01-01 00:04:30.000000',
-            ],
-            'chrono negative hour minute second' => [
-                'method' => 'fromChronoString',
-                'input' => '-1:05:30',
-                'reference' => '2021-01-01 02:00:00.000000',
-                'expected' => '2021-01-01 00:54:30.000000',
-            ],
-            'chrono negative fractional second' => [
-                'method' => 'fromChronoString',
-                'input' => '-12:28.5',
-                'reference' => '2021-01-01 00:20:00.000000',
-                'expected' => '2021-01-01 00:07:31.500000',
-            ],
-            'time negative with zero hour' => [
-                'method' => 'fromTimeString',
-                'input' => '-00:30',
-                'reference' => '2021-01-01 01:00:00.000000',
-                'expected' => '2021-01-01 00:30:00.000000',
-            ],
-            'time negative hour and minute' => [
-                'method' => 'fromTimeString',
-                'input' => '-01:30',
-                'reference' => '2021-01-01 05:00:00.000000',
-                'expected' => '2021-01-01 03:30:00.000000',
+                'chronometer' => '-00:00:28.5',
+                'expected' => 'PT28.5S',
             ],
         ];
     }