diff --git a/test/integration/smoke.test.ts b/test/integration/smoke.test.ts
index 9fed5856..bbbe20eb 100644
--- a/test/integration/smoke.test.ts
+++ b/test/integration/smoke.test.ts
@@ -16,7 +16,7 @@ describe("Smoke tests", () => {
 
   it("userAgent option", () => {
     const mock = fetchMock
-      .sandbox()
+      .createInstance()
       .getOnce("https://api.github.com/", (_url, { headers }) => {
         // @ts-ignore headers has wrong typing in fetch-mock 8.3.2
         expect(headers["user-agent"]).toMatch(/^my-app\/1.2.3 /);
@@ -27,7 +27,7 @@ describe("Smoke tests", () => {
     const octokit = new Octokit({
       userAgent: "my-app/1.2.3",
       request: {
-        fetch: mock,
+        fetch: mock.fetchHandler,
       },
     });
     return octokit.request("/");
@@ -35,12 +35,12 @@ describe("Smoke tests", () => {
 
   it("@octokit/plugin-rest-endpoint-methods", () => {
     const mock = fetchMock
-      .sandbox()
+      .createInstance()
       .getOnce("path:/repos/octocat/hello-world", { ok: true });
 
     const octokit = new Octokit({
       request: {
-        fetch: mock,
+        fetch: mock.fetchHandler,
       },
     });
 
@@ -58,7 +58,7 @@ describe("Smoke tests", () => {
 
   it("@octokit/plugin-request-log", () => {
     const mock = fetchMock
-      .sandbox()
+      .createInstance()
       .getOnce("path:/", { status: 200, body: {} })
       .getOnce("path:/", { status: 404, body: {} }, { overwriteRoutes: false });
 
@@ -72,7 +72,7 @@ describe("Smoke tests", () => {
     const octokit = new Octokit({
       log: consoleStub,
       request: {
-        fetch: mock,
+        fetch: mock.fetchHandler,
       },
     });
 
diff --git a/test/issues/881-redirect-url.test.ts b/test/issues/881-redirect-url.test.ts
index f4d2248b..68d2b029 100644
--- a/test/issues/881-redirect-url.test.ts
+++ b/test/issues/881-redirect-url.test.ts
@@ -9,7 +9,7 @@ describe("https://github.com/octokit/rest.js/issues/881", () => {
       "https://issue-881-codeload.github.com/octocat/Hello-World/legacy.tar.gz/master";
 
     const mock = fetchMock
-      .sandbox()
+      .createInstance()
       .headOnce(
         "https://api.github.com/repos/octocat/Hello-World/tarball/master",
         {
@@ -20,7 +20,7 @@ describe("https://github.com/octokit/rest.js/issues/881", () => {
 
     const octokit = new Octokit({
       request: {
-        fetch: mock,
+        fetch: mock.fetchHandler,
       },
     });