diff --git a/docker/Dockerfile b/docker/Dockerfile
index 945c7fe3e3..3feff79beb 100644
--- a/docker/Dockerfile
+++ b/docker/Dockerfile
@@ -162,6 +162,14 @@ RUN pip install multi-storage-client --no-deps
 COPY requirements.txt /tmp/requirements.txt
 RUN rm -rf /usr/lib/python3/dist-packages/jwt /usr/lib/python3/dist-packages/PyJWT* && pip install -r /tmp/requirements.txt
 
+# The apt copy shadows the pip one in ldconfig and the loader interleaves the two,
+# so transformer_engine gets a mixed set of libcudnn sub-libraries. The packages are
+# held, hence --allow-change-held-packages.
+RUN if [ "${ENABLE_CUDA_13}" = "1" ]; then CU=13; else CU=12; fi; \
+  apt-get remove -y --purge --allow-change-held-packages \
+    libcudnn9-cuda-${CU} libcudnn9-dev-cuda-${CU} libcudnn9-headers-cuda-${CU} \
+  && rm -rf /var/lib/apt/lists/*
+
 RUN if [ "${ENABLE_CUDA_13}" = "1" ]; then \
     pip install nvidia-cudnn-cu13==9.22.0.52; \
   else \