There's a great new blog post about how Azure Security Center (ASC) can automate the deployment of a web application firewall (WAF) to protect your servers:
https://azure.microsoft.com/en-us/blog/how-azure-security-center-helps-protect-your-servers-with-web...
Be sure to also check out the ASC Playbook referenced in the article:
https://gallery.technet.microsoft.com/ASC-Playbook-Protect-38bd47ff