Playing defense in the NFL is hard. A decade of rule tweaks that favor offenses — defensive holding penalties per game have almost doubled per year from 2006 to 2016, for example — produced the best league-wide offensive performances in NFL history in that time frame. Plus, the athletes on the offensive side of the ball are as talented as any group in NFL history. Imagine being forced to play basketball with a hand tied behind your back and then — surprise — you also find out your opponent is Michael Jordan. That’s what being a defender in the NFL can feel like in 2017.

Here is the problem, then, that the Dallas Cowboys and every other team has to solve: There were 49 wide receivers 6-foot-3 or taller who started a game last year. Guess how many starting defensive backs were that tall? Eleven.

Compare that to 1996, when only 17 receivers 6-foot-3 or taller started a game. It is a wonder that NFL teams don’t complete every pass in the modern era. Oh, wait, they basically do: Over the past two years, league-wide completion percentage has been at an all-time high at 63 percent.

The Cowboys, 26th in passing defense last year, have a potential solution to this problem that makes them perhaps the most intriguing defense in the league. You already know about Dak Prescott and Zeke Elliott, but if the defense’s new approach works and it becomes as efficient as the offense, they’ll be the unit the propels the Cowboys toward the Super Bowl.

So what makes them special? They can jump really high and really far.

“Being able to leap with the bigger guys is important and getting more important,” said Dallas secondary coach Joe Baker. “Because when you look at the league, there’s a lot more 6-foot-3, 6-foot-4 receivers and there are not many corners above 6-foot-2-and-a-half. So the smaller guy is going to be playing on defense; he’s got to be able to make up that difference somehow.”

The Cowboys’ secondary is basically entirely reworked this season after the departures of Brandon Carr, Barry Church, J.J. Wilcox, and Morris Claiborne. An Over The Cap study said Dallas had more roster turnover than all but one NFL team this offseason — and its secondary overhaul is a big part of that. Incumbent starting safety Byron Jones, whose 147-inch broad jump is the best in the history of the combine and unofficially, the world, and whose 44-inch vertical jump is the highest of any defensive back in the past eight years, will be filling a major role this year. His presumptive new starting safety partner, Jeff Heath, featured pro-day numbers that would have been top five in broad jump and top 10 in vertical jump among combine participants at his position during his draft year, had he been invited. The team’s second-round pick, Colorado’s Chidobe Awuzie, was tied for second among corners in broad jump. The big bet for 2017 is on athleticism.

According to Heath, there are plenty of benefits to a secondary filled with leapers. Most importantly: Since modern quarterbacks have become so efficient and accurate that they typically pass as far away from the defender as possible, a quick leap — either horizontally or vertically — gives the quarterback a smaller window to throw to and disrupts the timing. “It gets the quarterback uncomfortable,” Heath said. “The ball is never thrown to us. We have to be reactionary all the time, and the jumping ability comes in because these good quarterbacks are going to put it in a spot that is hard to get to no matter how good your positioning is.”

The value teams place on height now has dramatically changed the NFL. The Seattle Seahawks briefly solved the problem of ever-growing receivers by matching cornerbacks like 6-foot-4 Brandon Browner and 6-foot-3 Richard Sherman. The plan couldn’t last forever due to a simple supply issue. The inefficiencies the Seahawks had identified in bigger, slower cornerbacks, were no longer secrets, so a player like 6-foot-3 Stanley Jean-Baptiste went in the second round of the draft in 2014. Except Jean-Baptiste played just one year for the team that drafted him, the Saints, and just signed with his fifth team before he’s even begun his fourth NFL season. The tall-cornerback revolution never got off the ground because beyond Sherman the number of people who are both 6-foot-3 and agile enough to play defensive back is basically zero.

The second response to the receiver/defensive back height discrepancy got its start around 2015, when Jones, then a safety from UConn, started jumping in a gym in Florida. Jones’s trainer for the combine, Stefan Underwood of Exos, a sports training company, said the plan was for Jones, who was nursing a shoulder injury at the time, to just interview and do medical testing at the combine — until he started to jump. While still recovering from his injury, Jones jumped 11 feet, four inches in the broad jump during a workout — about three inches short of the combine record. Underwood yelled “holy crap!” and called Jones’s agent and suggested his client jump at the combine.

“I always like to underpromise and overdeliver — I never guarantee anything,” Underwood says. “But I basically told him, ‘I’d bet my year’s salary that Byron was going to break the record.’”

Jones did that — and he broke the world record for the broad jump in the process, too. He also won the vertical jump in his position group for good measure. In an era of increased emphasis on raw data, Jones said these numbers sent NFL teams scrambling back to the tape and ultimately took him from a likely mid-rounder to a first-round pick.

“It was a huge part — it propelled me into the national spotlight, scouts and coaches started looking more at my film,” Jones said of the leap. “It’s hard to measure the impact.”

But that’s what Bill Lotter is trying to do. He is a machine-learning expert who has consulted with an NFL team on combine research. He did one of the most comprehensive combine data studies ever, studying all the results from 2000 to 2011 and analyzing which drills correlate most with success for a given position. There was only one position, he said, in which vertical jumping most correlated with success: free safety, where Jones plays for Dallas.

“The average vertical jump for a free safety is 35.8,” Lotter said. “A good number would be 39 or over 40.”

Now, Lotter explains, this does not mean anyone who jumps high can be a great free safety, but it does mean that if you are a free safety and you can jump 40 inches in the air, you stand about a 5 percent better chance at having a good NFL career than a player who does not, according to his data. Five percent may not sound like a lot, but in the ultracompetitive draft world — where there are so many prospects that about 100 combine participants do not get drafted — even the smallest edge in predicting success is a boost to teams. However, teams also seem to be catching on, as 40-inch jumpers can also expect to be drafted about a half-round higher than those who can’t hit the same heights.

Underwood said the on-field advantages of having a jumper like Jones are fairly straightforward. Vertical jump helps you get in the air and broad jump shows horizontal movement. “Ultimately, jumping shows how much power you have in relation to your mass,” Underwood said.

Jones said he’s studied what jumping can bring to a defense: It cuts off both jump balls in the end zone and fades in the middle of the field. “The key for a defensive back on any throw is to get the ball at the highest point, and guys with good leaping ability can do that,” Jones said. “When the ball is in the air, they are not the offense — the offense is whoever gets to the ball first.”

Getting to the ball was a slight problem for Dallas’s defense in 2016. The defense had just nine interceptions last year — 27th in the NFL. Jones said coaches have been preaching turnovers this offseason. And Heath, of course, did his part in the playoffs:

Baker said the measurements are important and that Dallas marries them with the tape. Measurable data, like the leaping numbers, was slightly more important for a player like Heath, who attended Saginaw Valley State, where Baker said, “you’re not sure about the level of competition.”

Heath said he feels a team like this is well-equipped for its division. He specifically mentioned the need to keep up with 6-foot-4 Alshon Jeffery, now in Philadelphia.

“The league has changed even since I’ve come in,” said Heath, a fifth-year pro who has been a special teams ace in the past. “There’s always been big receivers, but now there’s a premium on it and they can run. Every team in our division has one. And that’s where all of this comes into play.”

Defense, in other words, is harder than ever. And the Cowboys may have figured out a way to keep up.