diff --git a/src/Symfony/Component/Cache/Tests/Adapter/AdapterTestCase.php b/src/Symfony/Component/Cache/Tests/Adapter/AdapterTestCase.php
index 01f17fdb8a72..60449e1d24bc 100644
--- a/src/Symfony/Component/Cache/Tests/Adapter/AdapterTestCase.php
+++ b/src/Symfony/Component/Cache/Tests/Adapter/AdapterTestCase.php
@@ -331,6 +331,19 @@ public function testNullByteInKey()
 
         $this->assertSame(123, $cache->getItem("a\0b")->get());
     }
+
+    public function testNumericKeysWorkAfterMemoryLeakPrevention()
+    {
+        $cache = $this->createCachePool(0, __FUNCTION__);
+
+        for ($i = 0; $i < 1001; ++$i) {
+            $cacheItem = $cache->getItem((string) $i);
+            $cacheItem->set('value-'.$i);
+            $cache->save($cacheItem);
+        }
+
+        $this->assertEquals('value-50', $cache->getItem((string) 50)->get());
+    }
 }
 
 class NotUnserializable
diff --git a/src/Symfony/Component/Cache/Traits/AbstractTrait.php b/src/Symfony/Component/Cache/Traits/AbstractTrait.php
index f4902917d38b..b047880661ff 100644
--- a/src/Symfony/Component/Cache/Traits/AbstractTrait.php
+++ b/src/Symfony/Component/Cache/Traits/AbstractTrait.php
@@ -290,7 +290,7 @@ private function getId($key): string
         $this->ids[$key] = $key;
 
         if (\count($this->ids) > 1000) {
-            array_splice($this->ids, 0, 500); // stop memory leak if there are many keys
+            $this->ids = \array_slice($this->ids, 500, null, true); // stop memory leak if there are many keys
         }
 
         if (null === $this->maxIdLength) {