Is there a way to externally block access to Taleo?

Summary:

My leadership would like to know if there is a way to block external access, meaning access outside of our company's network, to our Taleo systems?  We have Legacy SSO for our users so 99% of those that access the system are forced to be on the company's network to access Taleo. However, we do have the bypass SSO URLs for admins to use for testing and in case SSO ever fails (which it has in the past).

Content (required):

Is there a way to ensure admins, or anyone who has the bypass link, cannot use it outside of the company's network?  Is there a way to block the ****.taleo.net URLs from being accessed without the user first being authenticated through the company's network?