Sport exists in a paradox. There is “spirit of the game”, the uncoded ethics of conduct, played out in the media. And there are the rules. The two don’t always sit very comfortably.

In golf, ethics are probably more important than in any other sport. Without the hurly-burly contact of most other games, there is no room for heat-of-the-moment, getting-carried-away excuses. The competitive spirit must be kept in check.

Which makes the actions of the European player Suzann Pettersen so controversial. Close putts are conceded in matchplay golf – that’s what you do. So to call an opponent out for picking up their ball when just 18 inches from the cup is clearly bad. Her apology was a good idea (when it eventually came).

The funny thing is, I’ve watched golf matches where, as things get tense, short putts aren’t given. It’s understandable. It’s also part of the game to be able to put your opponent under pressure.

It’s also the letter of the law. Should players reject the law just because that’s what has gone before? Why should Australian cricket captain Steve Smith be criticised for the Ben Stokes appeal when he obstructed the field and used his hand to stop the ball hitting the stumps?

In the Stokes case, it was a debatable decision. So that’s what the umpires are for – to make the call. It is naive to think we can do away without referees at the top level of sport, and have players walk when out, make their own line calls, say when they have hand-balled and so on. Nice idea; ain’t gonna happen.

Which brings us to Diego Costa. Does he play within the spirit of the game? He certainly oversteps the rules of the game now and then. But is there a validity to being a wind-up merchant? England rugby hooker Brian Moore used to be praised for his ability to antagonise the French. Is Costa so different (even if his teammates also call him a cheat)?

And so to the best sports writing of the week:

RUGBY
World Cup! World Cup! WORLDCUUUUUP!
Japan’s win over South Africa was amazing on many levels. Here are a few other great rugby upsets.

How fair is the Rugby World Cup draw? (2011 was really bad).  And how Rugby always stiffs the smaller nations (such as Samoa).

Interesting piece on Sam Burgess: golden boy. I’d like to see more on him on the pitch in the World Cup.

Back in time: Remembering Jonah Lomu. And, the pain of 1991 (if you are English).

FOOTBALL
This piece is pre-Arsenal game, but a good read on Mourinho’s tricky season.

The Steven Gerrard problem: fitting him in. Now it’s LA’s turn.

Tenuous: Jeremy Corbyn plus economics equals Chelsea?

Doncha just HATE the Glazers?

How to identify goal scoring ability in football.

ALL
Can sportsmen be called geniuses?

TENNIS
The thoughtful Mr Agassi.

Djokovic and Federer: the greatest of all time?

Two weeks in New York: how the grand slam dream died.

GOLF
That Solheim Cup controversy; and how it worked for the US.

BRIDGE (yes, Bridge).
It’s a simple question: is it or is it not a sport?

NFL
The value of a good kicker just went up a lot.

Who doesn’t love a bit of Elo rankings to determine the best-ever?

What the NFL can learn from rugby.

F1
Have Mercedes lost it?

ATHLETICS
The Bolt paradox: the dirtier his sport, the brighter he shines.

BASKETBALL
Kareem Abdul-Jabbar: misunderstood?

That’s it, thanks for the suggestions, keep on sharing, and see you next Tuesday.