diff --git a/analyzers/tests/SonarAnalyzer.UnitTest/TestCases/AssertionsShouldBeComplete.FluentAssertions.CSharp8.cs b/analyzers/tests/SonarAnalyzer.UnitTest/TestCases/AssertionsShouldBeComplete.FluentAssertions.CSharp8.cs
index 9ce5a982177..dad424a6a48 100644
--- a/analyzers/tests/SonarAnalyzer.UnitTest/TestCases/AssertionsShouldBeComplete.FluentAssertions.CSharp8.cs
+++ b/analyzers/tests/SonarAnalyzer.UnitTest/TestCases/AssertionsShouldBeComplete.FluentAssertions.CSharp8.cs
@@ -10,8 +10,9 @@ public class Program
     public void StringAssertions()
     {
         var s = "Test";
-        s.Should();              // Noncompliant (no "ambiguous calls" compiler error as in C# 7)
+        s.Should();              // Noncompliant
         s?.Should();             // Noncompliant
+        s[0].Should();           // Noncompliant (no "ambiguous calls" compiler error as in C# 7)
         s?[0].Should();          // Noncompliant
         s.Should().Be("Test");   // Compliant
         s.Should()?.Be("Test");  // Compliant