diff --git a/src/coverlet.core/Coverage.cs b/src/coverlet.core/Coverage.cs
index 5904a96de..f7a86d39b 100644
--- a/src/coverlet.core/Coverage.cs
+++ b/src/coverlet.core/Coverage.cs
@@ -145,7 +145,7 @@ public CoverageResult GetCoverageResult()
                     }
                 }
 
-                modules.Add(result.ModulePath, documents);
+                modules.Add(Path.GetFileName(result.ModulePath), documents);
                 InstrumentationHelper.RestoreOriginalModule(result.ModulePath, _identifier);
             }
 
diff --git a/src/coverlet.core/CoverageResult.cs b/src/coverlet.core/CoverageResult.cs
index 2c8d60789..ed17451a7 100644
--- a/src/coverlet.core/CoverageResult.cs
+++ b/src/coverlet.core/CoverageResult.cs
@@ -1,3 +1,4 @@
+using System;
 using System.Collections.Generic;
 using System.IO;
 using System.Linq;
@@ -44,7 +45,7 @@ internal void Merge(Modules modules)
         {
             foreach (var module in modules)
             {
-                if (!this.Modules.Keys.Select(Path.GetFileName).Contains(Path.GetFileName(module.Key)))
+                if (!this.Modules.Keys.Contains(module.Key))
                 {
                     this.Modules.Add(module.Key, module.Value);
                 }