diff --git a/lib/propshaft/output_path.rb b/lib/propshaft/output_path.rb
index 6ac18cc4..df6687e5 100644
--- a/lib/propshaft/output_path.rb
+++ b/lib/propshaft/output_path.rb
@@ -53,7 +53,7 @@ def all_files_from_tree(path)
     end
 
     def extract_path_and_digest(digested_path)
-      digest = digested_path.to_s[/-([0-9a-f]{7,128})\.(?!digested)[^.]+\z/, 1]
+      digest = digested_path.to_s[/-([0-9a-f]{7,128})\.(?!digested)/, 1]
       path = digest ? digested_path.sub("-#{digest}", "") : digested_path
 
       [path, digest]
diff --git a/test/fixtures/output/one-f2e1ec15.txt.map b/test/fixtures/output/one-f2e1ec15.txt.map
new file mode 100644
index 00000000..0b44522d
--- /dev/null
+++ b/test/fixtures/output/one-f2e1ec15.txt.map
@@ -0,0 +1 @@
+One from first path map
\ No newline at end of file
diff --git a/test/propshaft/output_path_test.rb b/test/propshaft/output_path_test.rb
index 84342b5f..5210cf60 100644
--- a/test/propshaft/output_path_test.rb
+++ b/test/propshaft/output_path_test.rb
@@ -8,7 +8,8 @@ class Propshaft::OutputPathTest < ActiveSupport::TestCase
   setup do
     @manifest    = {
       ".manifest.json": ".manifest.json",
-      "one.txt": "one-f2e1ec14.txt"
+      "one.txt": "one-f2e1ec14.txt",
+      "one.txt.map": "one-f2e1ec15.txt.map"
     }.stringify_keys
     @output_path = Propshaft::OutputPath.new(Pathname.new("#{__dir__}/../fixtures/output"), @manifest)
   end
@@ -49,6 +50,19 @@ class Propshaft::OutputPathTest < ActiveSupport::TestCase
     FileUtils.rm(current) if File.exist?(current)
   end
 
+  test "clean keeps the correct number of versions regardless of the file extension" do
+    old     = output_asset("by_count.txt.map", "old", created_at: Time.now - 300)
+    current = output_asset("by_count.txt.map", "current", created_at: Time.now - 180)
+
+    @output_path.clean(1, 0)
+
+    assert File.exist?(current)
+    assert_not File.exist?(old)
+  ensure
+    FileUtils.rm(old) if File.exist?(old)
+    FileUtils.rm(current) if File.exist?(current)
+  end
+
   test "clean keeps all versions under a certain age" do
     old     = output_asset("by_age.txt", "old")
     current = output_asset("by_age.txt", "current")