diff --git a/.github/workflows/nightlies.yml b/.github/workflows/nightlies.yml
index 438fe26cb1ce..7e661ddf0070 100644
--- a/.github/workflows/nightlies.yml
+++ b/.github/workflows/nightlies.yml
@@ -54,11 +54,12 @@ jobs:
         run: |
           python -m pip install --upgrade pip setuptools wheel
           # c.f. https://github.com/Anaconda-Platform/anaconda-client/issues/540
-          python -m pip install git+https://github.com/Anaconda-Server/anaconda-client
+          python -m pip install git+https://github.com/Anaconda-Server/anaconda-client@be1e14936a8e947da94d026c990715f0596d7043
           python -m pip list
 
       - name: Upload wheels to Anaconda Cloud as nightlies
         run: |
           anaconda --token ${{ secrets.ANACONDA_ORG_UPLOAD_TOKEN }} upload \
             --user scipy-wheels-nightly \
+            --skip-existing \
             dist/matplotlib-*.whl