A former placekicker with the New York Giants, Lawrence Tynes, practiced for the fair catch free kick scenario many times during his career, but was surprised to see it converted Thursday night by the Los Angeles Chargers in their game against the Denver Broncos at Los Angeles.

Chargers kicker Cameron Dicker drilled a record-long 57-yard free kick just before halftime to spark Los Angeles to a 34-27 victory over the Broncos at Sof Fi Stadium. It was the first made free kick since Ray Wersching of the then-San Diego Chargers connected from 45 yards against the Buffalo Bills in 1976. The last attempt, which missed, was in 2019 by Joey Slye of the Carolina Panthers from 60 yards against the Tampa Bay Buccaneers. The previous longest successful previous fair catch free kick was from 52 yards by Paul Hornung of the Green Bay Packers in 1962.

While social media went berserk over the little known rule, Mr. Tynes was schooled on its options. He played on the Giants 2007 and 2011 Super Bowls teams and though he never got the opportunity to attempt such a kick coach Tom Coughlin made sure he was prepared for the possibility. “With coach Couglin we would go over this a few times per year,” Mr. Tynes told The New York Sun. “We were always well prepared for anything under Coach Coughlin.”

Mr. Tynes recalled the Arizona Cardinals attempting a free kick against the Giants in 2008. “I was never close to kicking one in my career,” he said.

One of the reasons it hasn’t happened in nearly 50 years is coaches are aware of the rule and don’t want to risk the chance of making the mistake Denver did.

The Broncos elected to punt with eight seconds left. Time expired on the play but Denver’s Tremon Smith was called for an interference penalty for making contact with the returner as he made a fair catch signal.  The ensuing 15 yard penalty gave the Chargers the ball at their own 43-yard line.

According to Rule 10, Section 2, Article 4 of the NFL rule book: “After a fair catch is made or is awarded as the result of fair catch interference, the receiving team has the option of putting the ball in play by a snap or fair catch kick (drop kick or place kick without a tee) from the spot of the catch or succeeding spot after enforcement of any applicable penalties (3-9 and 11-4-3). This includes the 15-yard penalty enforced from the receiving team’s 20-yard line as applicable if the fair catch is made or awarded in his end zone from fair catch interference or illegal contact with the receiver after he has made a fair catch.”

Chargers coach Jim Harbaugh chose to try the free kick. Mr. Harbaugh last attempted a fair catch kick in 2013 as the head coach of the San Francisco 49ers, but Phil Dawson was short from 71 yards.

“It’s my favorite rule in football,” he said. “I’ve been trying to get one of those every game. It’s the first one we’ve made.”

Charger special teams coordinator Ryan Ficken, who Mr. Harbaugh called a “situational savant,” practices the free kick frequently during the season, including this week and recognized the chance to try it. After taking a timeout to “get dialed in,” Mr. Dicker took the field. With a holder and no rushers on defense, the placekicker booted the ball like a kickoff sailing the ball through the uprights, cutting Denver’s lead to 21-13.

“It was awesome,” Mr. Dicker told reporters after the game. “It was funny to be in that scenario and just be like, ‘There’s no lineup there. This looks a little weird, but it was really cool.”

The interference penalty was crucial making it a 47-yard field instead of a 62-yarder, which still might have been in range. “The good thing about the free kick is you don’t have to go back eight yards from snap,” like a field goal,” Mr. Harbaugh said. “You get it right at the spot.”

That’s why the play is a rarity.

“At the end of the half or game and no time left you should kick it out of bounds or have your quarterback roll out and throw it as far as he can out of bounds so time expires,” Mr. Tynes said. “This takes away the fair catch free kick.”

Mr. Wersching told NBC News he was watching the game happy for Mr. Dicker. “I’ve had my run,” Mr. Wersching, 74, said. “It was good long time.”

Since it has been nearly 50 years since the last converted fair catch kick, many players on the field Thursday night weren’t exactly sure what was happening. “Everybody was trying to figure out what was going on,” Chargers linebacker Bud Dupree said, according to ESPN. “We knew he could make it. We just didn’t understand. Was it going to be a two-point or three-point, or did we get the ball on the 1? We didn’t know.”