xGenius: Expected Goals and the Science of Winning Football Matches

by James Tippett

'Eye-opening. An essential read for any football fan' – Jamie Carragher

A new, expanded and super-charged guide to Expected Goals (xG) analysis from the bestselling author of The Expected Goals Philosophy.

The concept of Expected Goals – or xG – has changed how we understand football. Every fan will have heard of xG, many will understand what it is, but few will know exactly how it's being used by football teams to improve their chances of winning matches.

xGenius explores the interplay between analysis, tactics, and decision-making. It seeks to put the sport of football under the microscope with the aim of getting closer to the ultimate truth of what makes players, managers and teams successful. What, ultimately, wins football matches.

Packed with examples from the Premier League and beyond, xGenius shows how xG and other performance analysis tools are helping answer previously unanswerable questions. Were Brighton the unluckiest team in recent history? What is 'The Timo Werner Paradox'? How many titles did Liverpool deserve to win under Jürgen Klopp? Is Son Heung-Min the greatest finisher in the modern era?

xGenius demonstrates how clubs and coaches are using data as a major tool to improve performances on the pitch. It reveals how xG helped Brighton and Brentford transform themselves into established Premier League clubs, and how such analysis was integral to Liverpool and Arsenal's renaissance in recent years.

As teams have realised the importance of amassing high xG numbers, the average shot distances in Europe's major leagues have plummeted, dead ball situations have become ever more important, and players who are able to accumulate large xG volumes have become increasingly valuable. Clubs have developed new systems, formations and strategies as they strive for 'big chance creation'.

xGenius shows how top-level football analysis is being carried out by the very best in the business. The insights explored in this book will change the way you watch football.

Genres: Football, Sports, Nonfiction, Soccer

272 pages, Paperback

Published October 8, 2024

Reviews

[Dominic Hull · Rating 3 out of 5]

A lot more basic than I expected, but it serves as a nice overview of how data and stats were used in football a few years ago. Not that much insight into new innovations or potential future developments, but that is valuable information I suppose. I'd have still liked to have seen some more theories or interviews with people who were working on it.

[Diogo · Rating 3 out of 5]

Disappointing, as the author never provides any real detail on how these statistical models are built — not even at a non-technical level. This seems to stem from his limited grasp of the technical aspects; he has been involved in the football betting and analytics world, but not as an analyst himself. This shows through, with the author often making mistakes in causal reasoning and statistics. For instance:

"Brentford estimate their set-piece expertise grants them (...) a positive swing of roughly 19.00(xG) per season. For context, Harry Kane averaged 19.34(xG) per season during his spell at Tottenham. Brentford have essentially added a Harry Kane-like presence to their team through simply spending more time thinking about and practising set pieces."

(No, they haven't — as the author himself explains earlier in the book, Kane only adds the incremental xG above what his replacement produces, not his full 19.34 xG.)

The data and anecdotes in the book still make it fairly engaging. But given its shallowness, I doubt any critical reader will find it truly compelling, even if it's only football they're looking for.

[Ernesto · Rating 5 out of 5]

Fantástico libro, cambia la forma de ver los partidos

[Zach · Rating 3 out of 5]

This is a good primer on expected goals (xG) and football analysis. Tippett does a good job covering the fundamentals, and I was pleased to see that he used actual game situations to describe how xG can alter perceptions of opportunities and goals. As a sport statistic novice, such as myself, the breakdown of the quality of the shot and the outcome was riveting and understandable.

But by the conclusion I felt somewhat abandoned. While there's much data and statistics, not much is said about how to actually implement it. I found myself asking throughout: what does it matter for coaches, for spectators, or even for bettors? The book excels at discussing the "what" and "why," yet is sparse on the "so what" and "now what." That had me leaving with the sense that I had learned something nifty without much idea of how to implement it in practice.

Overall, it's a good read if you're interested in learning something about analytics, although if you're looking for practical advice or to take definite next steps, then perhaps it's worth reading in conjunction with something more practical.

[Edd Cowlishaw · Rating 2 out of 5]

I was really looking forward to reading this book, however the information is very surface level. If you don't understand football metrics, then this book is brilliant, it does a good job of explaining each one and looks a little at the pros and cons of each and how they can be used in conjunction. However, if you were looking for something really insightful about the metrics, then it'll disappoint.

There is one short chapter which I thought stood out, and after looking up the author it appears to be from his own experiences. To me, I would actually be really interested in more of this.

The remaining chapters are speculative and used lots of quotes which are in the public domain to try and speculate about why clubs might have been successful applying the theory. Some inside sources would be really helpful and could really bring the metrics to life.

[Matt · Rating 3 out of 5]

Enjoyed reading this but it definitely felt like it could have been a condensed set of articles rather than a book, though I've felt the same way about most analytics books I've read. In that way the blog boys were right about one more things. Blogs posts are far superior for imparting this sort of information. Getting to see video while reading about the topics is just a lot easier to do.

The other issue is that there were a lot of generalities about how this is used, which is to be expected in a book written by a journalist and not someone in the soccer community. Would recommend for someone that would be hard pressed to find this information somewhere else. Would not recommend if you're already into advanced stats in sports.

[Matthew Evans · Rating 3 out of 5]

The first 100ish pages are a bore. Mostly because it doesn’t really talk analytics. It focused more about how important analytics are and kept referencing “Moneyball”.

The second half of the book is where this book is best. It focuses mainly on 3 teams whose systems focus on analytics; Brighton, Brentford, and Liverpool. Each of these team’s trajectories changed substantially when they focused on soccer analytics, especially xG (expected goals)and xA(expected assist). Brighton and Brentford powered their way into the Premier League and became regulars. While Liverpool went from a mediocre 10ish years into consistently fighting for a title.

I value xG and xA highly before reading this, but this book solidifies it as two of my main soccer analytics stat points I will always refer to.

[Turlough Booth · Rating 5 out of 5]

Thank you James for the incredible amount of hours this must have taken. Brilliantly read by Simon on the Spotify audiobook version. Would highly recommend to all football fans especially those who enjoy the data side of the game. This has quite a lot of cross over with Christoph Biermanns excellent “Football Hackers” but also James has included many more interesting ideas.
I would read Football hackers first then this book if you’re looking for football data insider knowledge.

[Travis Wyant · Rating 4 out of 5]

It was nice to go from a heavy name drop book to a book focused mostly on what people produce. I was also able to follow “characters” better as they weren’t obscure 1950s footballers. The data driven approach has reenergized the very thing that sparked my interest in college sports. I look forward to applying what I learned here to my season — it won’t be xG but still something data driven!

[brian cook · Rating 5 out of 5]

Soccer’s Moneyball book

If you’re like me the sport of soccer fascinates you. From its ever changing and non stop action to the romance of a last second winner. This book lays out far more than just expected goals but what teams are doing, how they are doing it, and what the future holds

Can’t recommend this book enough

[Dan · Rating 2 out of 5]

Despite being the second book on the subject from this author, it's still pitched at the basic level you might need to convince a pub bore that xG isn't game's gone wokery. Disappointing for anyone expecting something deeper, but maybe there just isn't much more interesting material to be mined from this subject.

[Will Kerr · Rating 5 out of 5]

xGenius is a game changer, I will not watch football in the same way again. This book demonstrates a deep analysis of the game and the important xG concept. A great insight into the world of football analytics. I'd highly recommend it to anyone keen to learn more about the beautiful game.

[Jono Suter · Rating 4 out of 5]

pretty good first half is a little bit lacking and drawn out then when it gets into the analytical stuff and actual developments it's a really interesting read, really lacking in sources at any point though, idk what's going on there

[Ben Curran · Rating 5 out of 5]

I didn't think The Expected Goals Philosophy was particularly well-written, but this one is much better and goes a lot further in explaining xG.

I would highly recommend xGenius.

[Chase · Rating 5 out of 5]

Another banger by James Tippett. Hopefully Sunderland are taking notes..

[Josh · Rating 5 out of 5]

The newest bible of football analytics is here - what a book 🙌

[Tom Manning · Rating 4 out of 5]

A really informative read. I hope someone writes the book that takes this to the next level but no one is gonna share that secret sauce

[Sebastian Waisbrot · Rating 5 out of 5]

This book is a great way of sharing statistical concepts with people who are not into math. It is well written, the examples are on point, and it is educational.

[G · Rating 4 out of 5]

Xgenius is the vastly improved version of the previous book xg philosophy. Much better organised and with more convincing arguments

[Miro · Rating 5 out of 5]

I must say, it was a real page-turner for me. This book helps me a lot, and when I become a Football Data Analyst later, this book will be one of the reasons.

[Karim Tejani · Rating 5 out of 5]

Every soccer fan who reads this book will have the time of their life.

[Solomon Mcharo · Rating 3 out of 5]

This is a good book.

[David Helms · Rating 5 out of 5]

Excellent explanation

Great breakdown of xG, with a layman's explanation with examples. For those wanting to get into this field, it's a must read.

[Ben Iverson · Rating 4 out of 5]

Do you like soccer and stats? Then you would love this book. Otherwise, it might not be for you. :)

[Magnus Holmark · Rating 4 out of 5]

Wished it was a bit more technical

[Simon · Rating 2 out of 5]

OK Read. Nothing special, but some interesting background stories to statistics in football.

Red about 2/3 before I got bored with it.