diff --git a/packages/astro/src/server/middleware.ts b/packages/astro/src/server/middleware.ts
index 1c2933e1eccc..fd3e99692d08 100644
--- a/packages/astro/src/server/middleware.ts
+++ b/packages/astro/src/server/middleware.ts
@@ -97,6 +97,7 @@ export const handleRequest: (options?: MiddlewareOptions) => MiddlewareResponseH
         },
         async span => {
           const originalResponse = await next();
+
           if (span && originalResponse.status) {
             span.setHttpStatus(originalResponse.status);
           }
@@ -110,13 +111,11 @@ export const handleRequest: (options?: MiddlewareOptions) => MiddlewareResponseH
             return originalResponse;
           }
 
-          const { body, ...restOfOriginalResponse } = originalResponse;
-
           // Type case necessary b/c the body's ReadableStream type doesn't include
           // the async iterator that is actually available in Node
           // We later on use the async iterator to read the body chunks
           // see https://github.com/microsoft/TypeScript/issues/39051
-          const originalBody = body as NodeJS.ReadableStream | null;
+          const originalBody = originalResponse.body as NodeJS.ReadableStream | null;
           if (!originalBody) {
             return originalResponse;
           }
@@ -126,13 +125,13 @@ export const handleRequest: (options?: MiddlewareOptions) => MiddlewareResponseH
               for await (const chunk of originalBody) {
                 const html = typeof chunk === 'string' ? chunk : new TextDecoder().decode(chunk);
                 const modifiedHtml = addMetaTagToHead(html, hub, span);
-                controller.enqueue(modifiedHtml);
+                controller.enqueue(new TextEncoder().encode(modifiedHtml));
               }
               controller.close();
             },
           });
 
-          return new Response(newResponseStream, restOfOriginalResponse);
+          return new Response(newResponseStream, originalResponse);
         },
       );
       return res;
diff --git a/packages/astro/test/server/middleware.test.ts b/packages/astro/test/server/middleware.test.ts
index 9be67cc481a0..058982f06cc6 100644
--- a/packages/astro/test/server/middleware.test.ts
+++ b/packages/astro/test/server/middleware.test.ts
@@ -259,7 +259,8 @@ describe('sentryMiddleware', () => {
       url: new URL('https://myDomain.io/users/'),
     };
 
-    const originalResponse = new Response('<p>no head</p>', {
+    const originalHtml = '<p>no head</p>';
+    const originalResponse = new Response(originalHtml, {
       headers: new Headers({ 'content-type': 'text/html' }),
     });
     const next = vi.fn(() => Promise.resolve(originalResponse));
@@ -267,7 +268,11 @@ describe('sentryMiddleware', () => {
     // @ts-expect-error, a partial ctx object is fine here
     const resultFromNext = await middleware(ctx, next);
 
-    expect(resultFromNext).toBe(originalResponse);
+    expect(resultFromNext?.headers.get('content-type')).toEqual('text/html');
+
+    const html = await resultFromNext?.text();
+
+    expect(html).toBe(originalHtml);
   });
 });