diff --git a/lib/propshaft/compiler/source_mapping_urls.rb b/lib/propshaft/compiler/source_mapping_urls.rb
index 0a32d902..b01b044a 100644
--- a/lib/propshaft/compiler/source_mapping_urls.rb
+++ b/lib/propshaft/compiler/source_mapping_urls.rb
@@ -3,7 +3,7 @@
 require "propshaft/compiler"
 
 class Propshaft::Compiler::SourceMappingUrls < Propshaft::Compiler
-  SOURCE_MAPPING_PATTERN = %r{(//|/\*)# sourceMappingURL=(.+\.map)(\s*?\*\/)?\s*?\Z}
+  SOURCE_MAPPING_PATTERN = %r{(//|/\*)# sourceMappingURL=(?:.*\/)?(.*\.map)(\s*?\*\/)?\s*?\Z}
 
   def compile(logical_path, input)
     input.gsub(SOURCE_MAPPING_PATTERN) { source_mapping_url(asset_path($2, logical_path), $1, $3) }
diff --git a/test/fixtures/assets/mapped/prefixed-source.js b/test/fixtures/assets/mapped/prefixed-source.js
new file mode 100644
index 00000000..b445f4ca
--- /dev/null
+++ b/test/fixtures/assets/mapped/prefixed-source.js
@@ -0,0 +1,2 @@
+var fun;
+//# sourceMappingURL=assets/source.js.map
diff --git a/test/fixtures/assets/mapped/prefixed-source.js.map b/test/fixtures/assets/mapped/prefixed-source.js.map
new file mode 100644
index 00000000..e69de29b
diff --git a/test/propshaft/compiler/source_mapping_urls_test.rb b/test/propshaft/compiler/source_mapping_urls_test.rb
index 1b10e4bf..0128eb7e 100644
--- a/test/propshaft/compiler/source_mapping_urls_test.rb
+++ b/test/propshaft/compiler/source_mapping_urls_test.rb
@@ -25,6 +25,11 @@ class Propshaft::Compiler::SourceMappingUrlsTest < ActiveSupport::TestCase
                  compile_asset(find_asset("nested/another-source.js", fixture_path: "mapped"))
   end
 
+  test "resolves prefix on source map filename" do
+    assert_match %r{//# sourceMappingURL=/assets/source.js-[a-z0-9]{40}\.map},
+                 compile_asset(find_asset("prefixed-source.js", fixture_path: "mapped"))
+  end
+
   test "missing source map" do
     assert_no_match %r{sourceMappingURL},
                     compile_asset(find_asset("sourceless.js", fixture_path: "mapped"))