The game between the Panthers and Buccaneers got a little confusing toward the end of the first half on Sunday when Carolina decided to take advantage of an obscure NFL rule that hadn't been used by any team in the league in more than five years.

With eight seconds left to play in the first half, the Buccaneers were facing a fourth-and-35 from their own 11-yard line, which was an obvious punting situation for Tampa Bay. With Bucs punter Bradley Pinion kicking out of his own end zone, the Panthers knew they were going to have a chance to try and pull off the rare "fair catch free kick."

This isn't some rule that the NFL invented for their slate of games in London, it's an actual rule that can be used by any team.

Basically, the rule goes like this: If a team fair catches a punt, they're allowed to attempt a free kick on the next play. The kick isn't a typical field goal, either. The defense has to line up 10 yards off the ball -- similar to a kickoff -- and they're not allowed to try and block the kick. The "free kick" is more like a kickoff, except the kicker has to attempt the field goal off the ground and there's also a holder (The kicker also has the option to dropkick the ball, but that almost never happens)

Here's how the NFL describes the rule:

"After a fair catch, the receiving team has the option to put the ball in play by a snap or a fair catch kick (field goal attempt), with fair catch kick lines established ten yards apart. All general rules apply as for a field goal attempt from scrimmage. The clock starts when the ball is kicked. (No tee permitted.)"

So how did this play out in an actual game?

After Pinion's punt, Brandon Zylstra called for a fair catch at the 50-yard line with just one second left to play in the first half, which meant the Panthers had time to run their free kick.

And since you're probably wondering, here's what the free kick looked like:

Panthers kicker Joey Slye wasn't able to take advantage of the free kick as he sent his 60-yard try wide right.

Although the team calling for the fair catch can take advantage of the free kick rule at any point during a game, it really only makes sense at the end of a half. If the Panthers had called for this fair catch with 20 seconds left in the half, they likely would have run a play or two to try and get the ball closer for a field goal attempt. Remember, the free kick is only an option on the very next play after a fair catch.

The fair catch kick rule is very rarely used in the NFL. The last player to attempt a fair catch field goal was Phil Dawson, who tried a 71-yarder for the 49ers in 2013. Slye's field goal attempt was actually only the fifth fair catch kick attempted in the NFL over the past 20 years.

The last time a kicker actually made a fair catch kick came back in 1976 when Ray Wersching hit one from 45-yards out for the Chargers in a game against the Bills. Since then, kickers have gone 0-for-9, with attempts ranging from 58 to 74 yards.

Although Slye didn't to come through on his fair catch kick, the Panthers still led the Bucs 17-7 at halftime. For an up-to-date look at the game being played in London, be sure to click here and follow along in our live blog.