diff --git a/tests/Unit/Math/BigInteger/TestCase.php b/tests/Unit/Math/BigInteger/TestCase.php
index 5b86645e..87addfd4 100644
--- a/tests/Unit/Math/BigInteger/TestCase.php
+++ b/tests/Unit/Math/BigInteger/TestCase.php
@@ -266,7 +266,7 @@ abstract class Unit_Math_BigInteger_TestCase extends PhpseclibTestCase
         $this->assertSame('18446744073709551616', (string) $y);
     }
 
-    public function testRandom()
+    public function testRandomTwoArgument()
     {
         $min = $this->getInstance(0);
         $max = $this->getInstance('18446744073709551616');
@@ -276,11 +276,21 @@ abstract class Unit_Math_BigInteger_TestCase extends PhpseclibTestCase
         // chosen it's just not that likely
         $this->assertTrue($rand1->compare($min) > 0);
         $this->assertTrue($rand1->compare($max) < 0);
+    }
 
-        $rand2 = $min->random($max);
+    public function testRandomOneArgument()
+    {
+        $min = $this->getInstance(0);
+        $max = $this->getInstance('18446744073709551616');
+
+        $rand1 = $min->random($max);
         $this->assertTrue($rand1->compare($min) > 0);
         $this->assertTrue($rand1->compare($max) < 0);
 
+        $rand2 = $max->random($min);
+        $this->assertTrue($rand2->compare($min) > 0);
+        $this->assertTrue($rand2->compare($max) < 0);
+
         $this->assertFalse($rand1->equals($rand2));
     }