diff --git a/tests/unit-tests/run-unit-tests.sh b/tests/unit-tests/run-unit-tests.sh
index 64c4526..c04d7d6 100755
--- a/tests/unit-tests/run-unit-tests.sh
+++ b/tests/unit-tests/run-unit-tests.sh
@@ -66,7 +66,7 @@ fi
 ${PKG_MAINT_TOOL} -v --namespace rpms --name osbuild --release "${DIST_GIT_RELEASE}" prep
 
 # Extract the Source0 basename without extension
-SRC_DIR=$(spectool --source 0 osbuild.spec | sed 's/.\+\(osbuild-[0-9]\+\)\.tar\.gz/\1/')
+SRC_DIR=$(spectool --source 0 osbuild.spec | sed -E 's|.*/([^/]*)\.tar\.gz$|\1|')
 
 cd "${SRC_DIR}"