I'm a bit of a football nerd. In particular, the rules. I may honestly hunt out an opportunity to explain why intentional safeties are more prevalent in Canadian football than American football as a part of game strategy.
But today we're here to talk about the 71-yard fair catch kick attempt tried by the San Francisco 49ers against the St. Louis Rams near the end of the first half of last night's game.
The fair catch kick (kind of a holdover rule from the early days of football, when it was a lot more similar to rugby) is probably my favorite obscure rule. I cannot explain the joys in my heart any time I hear about it being tried in high school, college or the pros.
Here's the simple explanation: Any time a team calls for and successfully fair catches a punt or kick (mostly this happens with punts), the team can either start a drive on offense like normal OR they have the option to attempt an uncontested field goal from the spot of the fair catch. So the other team can't try to block it.
ETA: There is no fair catch kick at the college level.
You don't see it often. Partially because a lot of people don't know about it, and also it really only makes sense to try it at the very end of a half when you don't have time to try and use your offense to move the ball at least closer for a shorter field goal attempt.
The last successful fair catch kick in the NFL was by Ray Wersching of the Chargers in 1976. Since then, 8 NFL attempts have attempted one and never made it. However, there's usually at least one done successfully in high school every year, partially benefitted by the fact the attempts are usually shorter (in the 50-yard-range) and high school kickers are allowed to use a tee while NFL requires a holder. Here's one from Tennessee in 2011.