THOUSAND OAKS – For anyone still worried about Robert Quinn’s health, it might be safe to exhale.

After missing half of last season because of a back injury, the Rams’ defensive end has started to resemble his former All-Pro self, inducing nightmares for opposing quarterbacks. Need to quantify his performance? Quinn has forced 17 fumbles since 2013, including two this season. No other player is really within striking distance.

“That’s one stat that he doesn’t get enough recognition for,” defensive line coach Mike Waufle said.

Quinn holds first place by a healthy margin, knocking out five more loose balls than Washington linebacker Ryan Kerrigan. Rams teammate Alec Ogletree has been productive too, racking up 11 forced fumbles since 2013 – the same number as J.J. Watt, the NFL’s three-time Defensive Player of the Year. Dolphins defensive end Cameron Wake has 10, while a slew of others – including Pro Bowlers Von Miller (Broncos) and Ezekiel Ansah (Lions) – have nine.

Quinn knew he was in the lead, though he hadn’t sought out the exact number. He said he most likely saw it mentioned when scrolling through Instagram on his phone.

Some of the success could be due to simple luck – right place, right time, right swing of the arm. Rarely does the NFL’s list of leaders in forced fumbles stay the same on a year-to-year basis.

That Quinn plays defensive end on the right side, facing the blind side of most quarterbacks, doesn’t hurt either.

“It’s a little bit easier to create some fumbles when the guy doesn’t see you coming,” he said.

But some amount of training likely factors in as well. The Rams’ coaching staff, particularly Waufle and defensive coordinator Gregg Williams, emphasize that their players develop a nose for the ball. Every Friday, the defensive line runs through ball drills, trying to make turnover production a habit. They want the defense to score points. Last Sunday, for example, Quinn swatted the ball out Jameis Winston’s hand, allowing Ethan Westbrooks to pick it up for a 77-yard touchdown to help beat the Buccaneers.

“You must work your craft, no matter how minor a detail it may be,” Quinn said. “Something’s always going to be important. … You never know what type of play or how the ball may bounce your way.”

Added Waufle: “When you get to the quarterback, what do you do? Are you getting the sack, making sure he’s down, or are you going for the football? If you don’t emphasize going for the football, you’re not going to get it.”

And then, there’s the natural talent. Waufle said Quinn reminds him of Osi Umenyiora, whom he had coached for six years. Now a part of the New York Giants’ Ring of Honor, Umenyiora once forced 19 fumbles over four seasons, one of which he missed because of a knee injury.

Likewise, Quinn and Ogletree have put up gaudy numbers despite their own ailments. The defensive end was limited to eight games in 2015, while the linebacker only appeared in four before he broke his fibula against the Cardinals (1-2), the same team the Rams (2-1) will visit this Sunday.

“Sometimes, it’s just instinct,” said Ogletree, who caused and recovered the fumble that clinched the Rams’ Week 2 win over the Seahawks. “Just recognizing what’s going on, having a feel for the ball – if you can get it out, or if you just need to make the tackle and call it a day. You could practice it, but at the same time, we joke about it all the time.

“They ask me how I do that. I’ll be like, ‘Sometimes, I don’t even know.’”

Contact the writer: jwang@scng.com