diff --git a/weekly.sh b/weekly.sh
index 347d9d9..b075521 100755
--- a/weekly.sh
+++ b/weekly.sh
@@ -3,7 +3,7 @@
 set -e
 set -x
 
-JENKINS_VERSION=$(curl -sq https://api.github.com/repos/jenkinsci/jenkins/tags | grep '"name":' | grep -E -o '\d+(\.\d+)+'  | uniq | sort --version-sort | tail -1)
+JENKINS_VERSION=$(curl -sq https://api.github.com/repos/jenkinsci/jenkins/tags | grep '"name":' | egrep -o '[0-9]+(\.[0-9]+)+'  | uniq | sort --version-sort | tail -1)
 echo "$JENKINS_VERSION"
 
 JENKINS_SHA=$(curl "http://repo.jenkins-ci.org/simple/releases/org/jenkins-ci/main/jenkins-war/${JENKINS_VERSION}/jenkins-war-${JENKINS_VERSION}.war.sha1")