diff --git a/mpa/modules/models/classifiers/sam_classifier.py b/mpa/modules/models/classifiers/sam_classifier.py
index 8a316564..af3d9356 100644
--- a/mpa/modules/models/classifiers/sam_classifier.py
+++ b/mpa/modules/models/classifiers/sam_classifier.py
@@ -106,9 +106,9 @@ def state_dict_hook(module, state_dict, *args, **kwargs):
         if backbone_type == 'OTEMobileNetV3':
             for k, v in state_dict.items():
                 if k.startswith('backbone'):
-                    k = k.replace('backbone.', '')
+                    k = k.replace('backbone.', '', 1)
                 elif k.startswith('head'):
-                    k = k.replace('head.', '')
+                    k = k.replace('head.', '', 1)
                     if '3' in k:  # MPA uses "classifier.3", OTE uses "classifier.4". Convert for OTE compatibility.
                         k = k.replace('3', '4')
                         if module.multilabel and not module.is_export:
@@ -118,9 +118,9 @@ def state_dict_hook(module, state_dict, *args, **kwargs):
         elif backbone_type == 'OTEEfficientNet':
             for k, v in state_dict.items():
                 if k.startswith('backbone'):
-                    k = k.replace('backbone.', '')
+                    k = k.replace('backbone.', '', 1)
                 elif k.startswith('head'):
-                    k = k.replace('head', 'output')
+                    k = k.replace('head', 'output', 1)
                     if not module.hierarchical and not module.is_export:
                         k = k.replace('fc', 'asl')
                         v = v.t()
@@ -129,7 +129,7 @@ def state_dict_hook(module, state_dict, *args, **kwargs):
         elif backbone_type == 'OTEEfficientNetV2':
             for k, v in state_dict.items():
                 if k.startswith('backbone'):
-                    k = k.replace('backbone.', '')
+                    k = k.replace('backbone.', '', 1)
                 elif k == 'head.fc.weight':
                     k = k.replace('head.fc', 'model.classifier')
                     if not module.hierarchical and not module.is_export: