diff --git a/src/NzbDrone.Core.Test/OrganizerTests/FileNameBuilderTests/CleanTitleFixture.cs b/src/NzbDrone.Core.Test/OrganizerTests/FileNameBuilderTests/CleanTitleFixture.cs
index d0cb085e7..23d0ab44e 100644
--- a/src/NzbDrone.Core.Test/OrganizerTests/FileNameBuilderTests/CleanTitleFixture.cs
+++ b/src/NzbDrone.Core.Test/OrganizerTests/FileNameBuilderTests/CleanTitleFixture.cs
@@ -66,7 +66,6 @@ namespace NzbDrone.Core.Test.OrganizerTests.FileNameBuilderTests
         [TestCase("backslash \\ backlash", "backslash backlash")]
         [TestCase("I'm the Boss", "Im the Boss")]
         //[TestCase("", "")]
-        //[TestCase("", "")]
         public void should_get_expected_title_back(string title, string expected)
         {
             _series.Title = title;
diff --git a/src/NzbDrone.Core.Test/ParserTests/NormalizeTitleFixture.cs b/src/NzbDrone.Core.Test/ParserTests/NormalizeTitleFixture.cs
index 29539d315..23a016305 100644
--- a/src/NzbDrone.Core.Test/ParserTests/NormalizeTitleFixture.cs
+++ b/src/NzbDrone.Core.Test/ParserTests/NormalizeTitleFixture.cs
@@ -113,5 +113,11 @@ namespace NzbDrone.Core.Test.ParserTests
                 dirty.CleanSeriesTitle().Should().Be(word + "wordword");
             }
         }
+
+        [Test]
+        public void should_not_clean_trailing_a()
+        {
+            "Tokyo Ghoul A".CleanSeriesTitle().Should().Be("tokyoghoula");
+        }
     }
 }
diff --git a/src/NzbDrone.Core/Parser/Parser.cs b/src/NzbDrone.Core/Parser/Parser.cs
index 7f13c0321..2628aec17 100644
--- a/src/NzbDrone.Core/Parser/Parser.cs
+++ b/src/NzbDrone.Core/Parser/Parser.cs
@@ -147,7 +147,7 @@ namespace NzbDrone.Core.Parser
         //Regex to detect whether the title was reversed.
         private static readonly Regex ReversedTitleRegex = new Regex(@"[-._ ](p027|p0801|\d{2}E\d{2}S)[-._ ]", RegexOptions.Compiled);
 
-        private static readonly Regex NormalizeRegex = new Regex(@"((?:\b|_)(?<!^)(a|an|the|and|or|of)(?:\b|_))|\W|_",
+        private static readonly Regex NormalizeRegex = new Regex(@"((?:\b|_)(?<!^)(a(?!$)|an|the|and|or|of)(?:\b|_))|\W|_",
                                                                 RegexOptions.IgnoreCase | RegexOptions.Compiled);
 
         private static readonly Regex FileExtensionRegex = new Regex(@"\.[a-z0-9]{2,4}$",