This beautiful game would be very ugly if offside didn't exist. At the World Cup, you'll see it often.

The law governing its modern application has 45 clauses and runs to more than 1,000 words. A former Premier League referee ...

Julian Quinones was beyond the last Ecuador defender. Despite that, the Mexican winger wasn't called offside. Half a field ...

There was still a defender behind the ball when Iran scored the goal that seemed like it would get them a FIFA World Cup win ...

The flag is up! We explain what that means and why one of soccer's most important rules is also one of the toughest to see live.

The biggest single culprit in Iran’s failure to advance to the knockout phase is a weird idiosyncracy to the offside law that ...

World Cup soccer is back again, which means one of the most controversial calls in sports is returning, as well. The offside rule has caused some of the most frustrating moments ever in soccer and is ...

Micheal Barwegan is part of an all-Canadian crew at this World Cup, and says the new offside system makes his job easier in some ways ...