The blueprint is already established: In 1992, Congress amended the Cable Act to protect independent cable networks against discrimination by vertically integrated cable operators.
Once an agency is designated with the authority to police Google and other vertically integrated search engines (Bing included), website rivals could pursue individual discrimination claims just like the NFL. Importantly, website rivals would have to fund these battles, not with taxpayer money (of which millions were likely spent by the FTC in its antitrust investigation of Google), but with their own resources.