diff --git a/packages/next/next-server/server/next-server.ts b/packages/next/next-server/server/next-server.ts
index 8aa3adc1e1c5a..c7ccd7113208d 100644
--- a/packages/next/next-server/server/next-server.ts
+++ b/packages/next/next-server/server/next-server.ts
@@ -369,10 +369,9 @@ export default class Server {
       // interpolate dynamic params and normalize URL if needed
       if (pageIsDynamic) {
         let params: ParsedUrlQuery | false = {}
-        const paramsResult = utils.normalizeDynamicRouteParams({
-          ...parsedUrl.query,
-          ...query,
-        })
+
+        Object.assign(parsedUrl.query, query)
+        const paramsResult = utils.normalizeDynamicRouteParams(parsedUrl.query)
 
         if (paramsResult.hasValidParams) {
           params = paramsResult.params
@@ -407,6 +406,7 @@ export default class Server {
             pathname: matchedPathname,
           })
         }
+
         Object.assign(parsedUrl.query, params)
         utils.normalizeVercelUrl(req, true)
       }
diff --git a/test/integration/required-server-files/pages/api/optional/[[...rest]].js b/test/integration/required-server-files/pages/api/optional/[[...rest]].js
new file mode 100644
index 0000000000000..a5395a602d14c
--- /dev/null
+++ b/test/integration/required-server-files/pages/api/optional/[[...rest]].js
@@ -0,0 +1,7 @@
+export default (req, res) => {
+  console.log(req.url, 'query', req.query)
+  res.json({
+    url: req.url,
+    query: req.query,
+  })
+}
diff --git a/test/integration/required-server-files/pages/optional-ssg/[[...rest]].js b/test/integration/required-server-files/pages/optional-ssg/[[...rest]].js
new file mode 100644
index 0000000000000..dbe91169f2a77
--- /dev/null
+++ b/test/integration/required-server-files/pages/optional-ssg/[[...rest]].js
@@ -0,0 +1,20 @@
+export const getStaticProps = ({ params }) => {
+  return {
+    props: {
+      random: Math.random(),
+      params: params || null,
+    },
+    revalidate: 1,
+  }
+}
+
+export const getStaticPaths = () => {
+  return {
+    paths: [],
+    fallback: true,
+  }
+}
+
+export default function Page(props) {
+  return <p id="props">{JSON.stringify(props)}</p>
+}
diff --git a/test/integration/required-server-files/pages/optional-ssp/[[...rest]].js b/test/integration/required-server-files/pages/optional-ssp/[[...rest]].js
new file mode 100644
index 0000000000000..53a840b79e21d
--- /dev/null
+++ b/test/integration/required-server-files/pages/optional-ssp/[[...rest]].js
@@ -0,0 +1,13 @@
+export const getServerSideProps = ({ query, params }) => {
+  return {
+    props: {
+      random: Math.random(),
+      query: query,
+      params: params || null,
+    },
+  }
+}
+
+export default function Page(props) {
+  return <p id="props">{JSON.stringify(props)}</p>
+}
diff --git a/test/integration/required-server-files/test/index.test.js b/test/integration/required-server-files/test/index.test.js
index f5a0cafd9dfd9..399fcfedbc748 100644
--- a/test/integration/required-server-files/test/index.test.js
+++ b/test/integration/required-server-files/test/index.test.js
@@ -448,4 +448,58 @@ describe('Required Server Files', () => {
     expect(errors.length).toBe(1)
     expect(errors[0].message).toContain('gsp hit an oops')
   })
+
+  it('should normalize optional values correctly for SSP page', async () => {
+    const res = await fetchViaHTTP(
+      appPort,
+      '/optional-ssp',
+      { rest: '', another: 'value' },
+      {
+        headers: {
+          'x-matched-path': '/optional-ssp/[[...rest]]',
+        },
+      }
+    )
+
+    const html = await res.text()
+    const $ = cheerio.load(html)
+    const props = JSON.parse($('#props').text())
+    expect(props.params).toEqual({})
+    expect(props.query).toEqual({ another: 'value' })
+  })
+
+  it('should normalize optional values correctly for SSG page', async () => {
+    const res = await fetchViaHTTP(
+      appPort,
+      '/optional-ssg',
+      { rest: '', another: 'value' },
+      {
+        headers: {
+          'x-matched-path': '/optional-ssg/[[...rest]]',
+        },
+      }
+    )
+
+    const html = await res.text()
+    const $ = cheerio.load(html)
+    const props = JSON.parse($('#props').text())
+    expect(props.params).toEqual({})
+  })
+
+  it('should normalize optional values correctly for API page', async () => {
+    const res = await fetchViaHTTP(
+      appPort,
+      '/api/optional',
+      { rest: '', another: 'value' },
+      {
+        headers: {
+          'x-matched-path': '/api/optional/[[...rest]]',
+        },
+      }
+    )
+
+    const json = await res.json()
+    expect(json.query).toEqual({ another: 'value' })
+    expect(json.url).toBe('/api/optional?another=value')
+  })
 })