diff --git a/.github/workflows/check-type-sizes.yml b/.github/workflows/check-type-sizes.yml
index 219741b8e..f83262e8c 100644
--- a/.github/workflows/check-type-sizes.yml
+++ b/.github/workflows/check-type-sizes.yml
@@ -83,9 +83,11 @@ jobs:
       shell: bash
       run: |
         for name in old new; do
-          cd ${name}
-          tar xjf sizes-${{ runner.os }}-${{ matrix.arch }}-${name}.tar.bz2
-          cd ..
+          tarball=${name}/sizes-${{ runner.os }}-${{ matrix.arch }}-${name}.tar.bz2
+          if [ -f "${tarball}" ]; then
+            tar xjf "${tarball}" -C ${name}
+            rm "${tarball}"
+          fi
         done
         old/xml-dump-type-sizes > sizes-old.txt
         new/xml-dump-type-sizes > sizes-new.txt