diff --git a/packages/x-data-grid/src/hooks/utils/useGridApiRef.ts b/packages/x-data-grid/src/hooks/utils/useGridApiRef.ts
index 2cf0d87f9bfa1..a423dfea3a815 100644
--- a/packages/x-data-grid/src/hooks/utils/useGridApiRef.ts
+++ b/packages/x-data-grid/src/hooks/utils/useGridApiRef.ts
@@ -6,4 +6,5 @@ import { GridApiCommunity } from '../../models/api/gridApiCommunity';
  * Hook that instantiate a [[GridApiRef]].
  */
 export const useGridApiRef = <Api extends GridApiCommon = GridApiCommunity>(): ApiRef<Api> =>
+  // TODO v8: initialize with null (see https://github.com/mui/mui-x/issues/16135#issuecomment-2589395230 and https://github.com/mui/mui-x/issues/16000#issuecomment-2567820735)
   useRef<Api>({} as Api);
diff --git a/packages/x-internals/src/apiRef/apiRef.tsx b/packages/x-internals/src/apiRef/apiRef.tsx
index 999b1b1db829d..ac53cb7815296 100644
--- a/packages/x-internals/src/apiRef/apiRef.tsx
+++ b/packages/x-internals/src/apiRef/apiRef.tsx
@@ -1,9 +1,11 @@
 import * as React from 'react';
 import reactMajor from '../reactMajor';
 
+// in React 19 useRef requires a parameter, so () => infer R will not match anymore
 export type ApiRef<T> = typeof React.useRef<T> extends () => infer R
   ? R extends React.MutableRefObject<infer M | undefined>
-    ? React.MutableRefObject<M>
+    ? // In v7 we remove the possibility of undefined for MutableRefObject (see https://github.com/mui/mui-x/issues/16135#issuecomment-2589395230)
+      React.MutableRefObject<M>
     : R
   : React.RefObject<T>;