diff --git a/CHANGELOG.md b/CHANGELOG.md
index a90b3a0a..dfd7aef4 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Fixed
+
+- Crash when doing `recyclarr sync` with no `reset_unmatched_scores` present.
+
 ## [5.3.0] - 2023-08-21
 
 ### Added
diff --git a/src/Recyclarr.TrashLib/Config/Parsing/ConfigYamlMapperProfile.cs b/src/Recyclarr.TrashLib/Config/Parsing/ConfigYamlMapperProfile.cs
index a13bab1b..ba311f74 100644
--- a/src/Recyclarr.TrashLib/Config/Parsing/ConfigYamlMapperProfile.cs
+++ b/src/Recyclarr.TrashLib/Config/Parsing/ConfigYamlMapperProfile.cs
@@ -23,7 +23,8 @@ public class ConfigYamlMapperProfile : Profile
             .ForMember(x => x.UpgradeAllowed, o => o.MapFrom(x => x.Upgrade!.Allowed))
             .ForMember(x => x.UpgradeUntilQuality, o => o.MapFrom(x => x.Upgrade!.UntilQuality))
             .ForMember(x => x.UpgradeUntilScore, o => o.MapFrom(x => x.Upgrade!.UntilScore))
-            .ForMember(x => x.QualitySort, o => o.NullSubstitute(QualitySortAlgorithm.Top));
+            .ForMember(x => x.QualitySort, o => o.NullSubstitute(QualitySortAlgorithm.Top))
+            .ForMember(x => x.ResetUnmatchedScores, o => o.UseDestinationValue());
 
         CreateMap<ServiceConfigYaml, ServiceConfiguration>()
             .ForMember(x => x.InstanceName, o => o.Ignore());
diff --git a/src/tests/Recyclarr.Cli.Tests/AutoMapperConfigurationTest.cs b/src/tests/Recyclarr.Cli.Tests/AutoMapperConfigurationTest.cs
index dec620ad..152bc304 100644
--- a/src/tests/Recyclarr.Cli.Tests/AutoMapperConfigurationTest.cs
+++ b/src/tests/Recyclarr.Cli.Tests/AutoMapperConfigurationTest.cs
@@ -11,6 +11,9 @@ public class AutoMapperConfigurationTest : CliIntegrationFixture
     public void Automapper_config_is_valid()
     {
         var mapper = Resolve<MapperConfiguration>();
+        // Build an execution plan like:
+        // var plan = mapper.BuildExecutionPlan(typeof(QualityProfileConfigYaml), typeof(QualityProfileConfig));
+        // And do `plan.ToReadableString()` in the Debug Expressions/Watch
         mapper.AssertConfigurationIsValid();
     }
 }
diff --git a/src/tests/Recyclarr.TrashLib.Tests/Config/Parsing/ConfigYamlMapperProfileTest.cs b/src/tests/Recyclarr.TrashLib.Tests/Config/Parsing/ConfigYamlMapperProfileTest.cs
index 542e46c1..517b9d51 100644
--- a/src/tests/Recyclarr.TrashLib.Tests/Config/Parsing/ConfigYamlMapperProfileTest.cs
+++ b/src/tests/Recyclarr.TrashLib.Tests/Config/Parsing/ConfigYamlMapperProfileTest.cs
@@ -41,4 +41,15 @@ public class ConfigYamlMapperProfileTest
 
         result.QualitySort.Should().Be(QualitySortAlgorithm.Top);
     }
+
+    [Test]
+    public void Non_null_reset_unmatched_scores_when_source_is_null()
+    {
+        var yaml = new QualityProfileConfigYaml();
+
+        var mapper = CreateMapper();
+        var result = mapper.Map<QualityProfileConfig>(yaml);
+
+        result.ResetUnmatchedScores.Should().BeEquivalentTo(new ResetUnmatchedScoresConfig());
+    }
 }