diff --git a/branch-release/branch_release.sh b/branch-release/branch_release.sh
index 3999ceb..d49a7ab 100755
--- a/branch-release/branch_release.sh
+++ b/branch-release/branch_release.sh
@@ -31,7 +31,7 @@ fi
 TAG="$( echo "$GITHUB_REF" | sed -e 's/refs\/tags\///' )"
 
 # Trim patch number from tag '19.3.11' => '19.3'
-RELEASE_NUM="$( echo "$TAG" | grep -oE '([0-9]+\.[0-9]+)' )"
+RELEASE_NUM="$( echo "$TAG" | grep -oE '(^[0-9]+\.[0-9]+)' )"
 
 if [ -z "${RELEASE_NUM:-}" ]; then
 	echo "Tag does not appear to be for a release: ${TAG}" >&2