diff --git a/src/utils/matching/matchRequestUrl.test.ts b/src/utils/matching/matchRequestUrl.test.ts
index 5ffdcfc92..473e767dc 100644
--- a/src/utils/matching/matchRequestUrl.test.ts
+++ b/src/utils/matching/matchRequestUrl.test.ts
@@ -87,13 +87,25 @@ describe('coercePath', () => {
     )
   })
 
-  test('escapes the semicolon in protocol', () => {
+  test('escapes the colon in protocol', () => {
     expect(coercePath('https://example.com')).toEqual('https\\://example.com')
     expect(coercePath('https://example.com/:userId')).toEqual(
       'https\\://example.com/:userId',
     )
     expect(coercePath('http://localhost:3000')).toEqual(
-      'http\\://localhost:3000',
+      'http\\://localhost\\:3000',
+    )
+  })
+
+  test('escapes the colon in port', () => {
+    expect(coercePath('https://example.com:1234')).toEqual(
+      'https\\://example.com\\:1234',
+    )
+    expect(coercePath('https://example.com:1234/:userId')).toEqual(
+      'https\\://example.com\\:1234/:userId',
+    )
+    expect(coercePath('https://example.com:1234/:5678')).toEqual(
+      'https\\://example.com\\:1234/:5678',
     )
   })
 })
diff --git a/src/utils/matching/matchRequestUrl.ts b/src/utils/matching/matchRequestUrl.ts
index 61618e440..cdd4cbbeb 100644
--- a/src/utils/matching/matchRequestUrl.ts
+++ b/src/utils/matching/matchRequestUrl.ts
@@ -42,6 +42,11 @@ export function coercePath(path: string): string {
        * @see https://github.com/pillarjs/path-to-regexp/issues/259
        */
       .replace(/^([^\/]+)(:)(?=\/\/)/g, '$1\\$2')
+      /**
+       * Escape the port so that "path-to-regexp" can match
+       * absolute URLs including port numbers.
+       */
+      .replace(/((?::)(?:[0-9]+))/g, '\\$1')
   )
 }