diff --git a/packages/jest-cli/src/TestSequencer.js b/packages/jest-cli/src/TestSequencer.js
index c910aabe003e..d19ae95f2f1c 100644
--- a/packages/jest-cli/src/TestSequencer.js
+++ b/packages/jest-cli/src/TestSequencer.js
@@ -69,8 +69,8 @@ export default class TestSequencer {
   // fastest results.
   sort(tests: Array<Test>): Array<Test> {
     const stats = {};
-    const fileSize = test =>
-      stats[test.path] || (stats[test.path] = fs.statSync(test.path).size);
+    const fileSize = ({path, context: {hasteFS}}) =>
+      stats[path] || (stats[path] = hasteFS.getSize(path) || 0);
     const hasFailed = (cache, test) =>
       cache[test.path] && cache[test.path][0] === FAIL;
     const time = (cache, test) => cache[test.path] && cache[test.path][1];
diff --git a/packages/jest-cli/src/__tests__/test_sequencer.test.js b/packages/jest-cli/src/__tests__/test_sequencer.test.js
index cab3a8ce4218..6ee46df7577a 100644
--- a/packages/jest-cli/src/__tests__/test_sequencer.test.js
+++ b/packages/jest-cli/src/__tests__/test_sequencer.test.js
@@ -23,6 +23,9 @@ const context = {
     cacheDirectory: '/cache',
     name: 'test',
   },
+  hasteFS: {
+    getSize: path => path.length,
+  },
 };
 
 const secondContext = {
@@ -31,6 +34,9 @@ const secondContext = {
     cacheDirectory: '/cache2',
     name: 'test2',
   },
+  hasteFS: {
+    getSize: path => path.length,
+  },
 };
 
 const toTests = paths =>
@@ -45,7 +51,6 @@ beforeEach(() => {
 
   fs.readFileSync = jest.fn(() => '{}');
   fs.existsSync = () => true;
-  fs.statSync = jest.fn(filePath => ({size: filePath.length}));
   fs.writeFileSync = jest.fn();
 });