But after the Rams' offense stalled on the Arizona Cardinals' 2-yard line Sunday, Hekker trotted off the sideline and lined up for his first attempt in more than a decade.
The 20-yard kick split the uprights, and the Rams took an 11-0 lead in what would eventually become a 34-0 shutout.
"A little nerve-racking," Hekker said of the kick.
Moments before the pregame coin toss, special teams coordinator John Fassel notified coach Sean McVay that Pro Bowl kicker Greg Zuerlein suffered a groin injury during pregame warm-ups and would not be immediately available to play, if at all.
"That changed our approach right away," McVay said, adding, "That definitely affected the decision-making."
With receiver Cooper Kupp as his holder, Hekker, a four-time Pro Bowl selection as a punter, handled kickoff duties, kicked a field goal and also kicked an extra point. He also punted twice for 102 yards, placing one punt inside the 20-yard line.
"I can't imagine thinking you're going to punt the whole game and then like, 'Hey Johnny, you're going to kick field goals, too,'" quarterback Jared Goff said. "... No one flinched."
Hekker was awarded a game ball for his efforts.
"I've been watching the best kicker in the NFL week in and week out, watching Greg practice," Hekker said. "I just tried to emulate him the best I could."
McVay's decision to attempt a fourth-down conversion in the first quarter appeared initially as a gutsy playcall with the Rams facing fourth-and-1 at the Cardinals' 45-yard line. But left guard Rodger Saffold was called for a false start, which moved the ball back, and Hekker was brought on to punt.
It soon became apparent that McVay's decision-making was driven by Zuerlein's absence, rather than the playbook.
In the second quarter, running back Todd Gurley II converted a fourth-and-1 at the Cardinals' 1-yard line for a touchdown, then followed with a dive across the goal line for a two-point conversion as the Rams took an 8-0 lead.
"I didn't even know Greg was out until like the second quarter, honestly," Gurley said. "We were still on the field after we scored and we just found out we had to go for two."
The Rams were 2-for-4 on fourth-down conversions. They converted all three of their two-point attempts. Gurley ran for the first two, and backup running back Malcolm Brown caught a pass for the third.
"To be able to execute -- those are some tough-earned yards, a lot of plays in the tight-red area where things are condensed in and jumbled down in there," McVay said. "The guys that made the plays, it was tough running the football but a lot of those yards were hard-earned yards."
McVay said he was uncertain how long Zuerlein would be sidelined.
Zuerlein made four of five field goal attempts in a Week 1 victory over the Oakland Raiders. He connected on kicks from 20, 28, 55 and 20 yards. His lone miss was from 46 yards on the infield dirt at Oakland-Alameda County Coliseum.
Last season, Zuerlein led the NFL in scoring, averaging 11 points per game, but was sidelined after a Week 15 victory over the Seattle Seahawks and underwent season-ending back surgery.
Ficken was on the Rams' roster through training camp and the preseason, but did not make the final cut and was not signed to the practice squad. He is currently a free agent.
"Certainly that's an option for us," McVay said when asked about Ficken. "Sam came in, did a nice job. If he does have to fill in for Greg, for however long a period of time that is, but as of right now we'll find out and then we'll move forward accordingly."