The NFL rulebook is filled with weird technicalities that can make it hard to explain the sport to first-time viewers.

Good luck explaining to a new fan in London what happened at the end of the first half Sunday between the Carolina Panthers and Tampa Bay Buccaneers.

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With just one second remaining in the second quarter, the Panthers attempted the league’s first fair-catch kick in over six years, although kicker Joey Slye just missed a chance to put three more points on the board.

The Panthers shouldn’t have even had the chance to score. This was only possible since a holding penalty and three false starts backed the Bucs up to their own 11 with eight seconds left in the half, and Bradley Pinion sent a punt just 39 yards.

Little-known rule could have ballooned Panthers’ lead

Most fans aren’t familiar with fair catch kicks, possibly because there hasn’t been one since Phil Dawson attempted it on Sept. 26, 2013.

All NFL fans know that teams can kick a field goal by snapping the ball about 8 yards back and holding it. That’s the simple one. But if they call a fair catch on a punt, they may attempt a free kick from the line of scrimmage on the very next play with the defense standing at least 10 yards back.

Unfortunately, it was all for naught as Slye, whose career long is from 55 yards, missed wide right. Still, it was a chance to share one of the most quirky rules in the league with a new set of fans. There’s a long history of the obscure play with some funny footage.

No team has made a free-kick attempt in over 40 years

Panthers head coach Ron Rivera is 57, and he was still in high school the last time a team made a free-kick attempt. That honor belongs to San Diego Chargers kicker Ray Wersching, who made one from 45 yards out on Nov. 21, 1976.

There have been only six successful free-kick attempts since Curly Lambeau made one in 1921. Even then, the longest successful one came from Green Bay’s Paul Hornung from 52 yards out in 1964.

The last eight attempts during the regular season have all been unsuccessful, although many were long-shots. Five of them came from 68 yards or longer with just seconds remaining in the first half.

Because the rule is so obscure, some coaches didn’t even know how it worked. On Sept. 22, 1999, Dallas Cowboys coach Chan Gailey told punt returner Wayne McGarity to fair catch a punt, which he did on the Atlanta Falcons’ 47. But he didn't realize he could make an attempt with no time left on the clock, so the Cowboys missed out on a chance to add three points.

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