Mathematical sports betting is already a huge thing

There is a lot of literature and research in the field of professional gambling and modelling of sporting fixtures. There are several dedicated firms, such as ATASS, Starlizard, and Sporting advantage are three examples. Also, several big hedge funds now recruit for sports researchers and traders. With all that being said, I think you were either googling the wrong things, or didn't know how to filter out the relevant results. As the field is highly mathematical and statistical, don't be surprised if you see things which seem highly scientific or numeric. Furthermore, all the low-hanging fruit has already been picked, and making money with a mathematical approach will require a high level of expertise and competence with statistics and likely programming too.

An example introductory paper

A nice paper to introduce someone to the ideas behind a mathematical approach to modelling sports is:

Modelling association football scores and inefficiencies in the football betting market
--- Dixon and Coles (1997)

This models a football team's performance by a Poisson process and produces a strategy for placing bets and proved highly profitable in their tests. Although, don't expect the bookmaker's odd