diff --git a/moabb/evaluations/evaluations.py b/moabb/evaluations/evaluations.py
index bc52bda1e..046bd427c 100644
--- a/moabb/evaluations/evaluations.py
+++ b/moabb/evaluations/evaluations.py
@@ -260,10 +260,25 @@ def _evaluate_subject(
                 if isinstance(X, BaseEpochs):
                     scorer = get_scorer(self.paradigm.scoring)
                     acc = list()
-                    X_ = X[ix]
-                    y_ = y[ix] if self.mne_labels else y_cv
                     for cv_ind, (train, test) in enumerate(cv.split(X_, y_)):
                         cvclf = clone(grid_clf)
+
+                        valid_split = 0.2
+                        for s_cvclf in cvclf.steps:
+                            if "validation_split" in s_cvclf[1]._get_param_names():
+                                valid_split = s_cvclf[1].validation_split
+                        valid_split = 1.0 - np.floor(
+                            len(train) * (1.0 - valid_split)
+                        ) / len(train)
+
+                        cv_tv = StratifiedKFold(
+                            int(np.round(1.0 / valid_split)),
+                            shuffle=True,
+                            random_state=self.random_state,
+                        )
+                        (train_t, train_v) = next(cv_tv.split(X_[train], y_[train]))
+                        train = np.concatenate((train[train_t], train[train_v]), axis=0)
+
                         cvclf.fit(X_[train], y_[train])
                         acc.append(scorer(cvclf, X_[test], y_[test]))