ENGLEWOOD, Colo. --Not since the AFL-NFL merger, when the NFL exploded from 16 to 26 teams, had a single offensive line produced three first-team All-Pros until the Dallas Cowboys did so last year.

Left tackle Tyron Smith, right guard Zack Martin and center Travis Frederick all earned the honor.

"If you look at that offensive line, it's an all-star offensive line," outside linebacker Von Miller said.

Their production was a massive reason why running back Ezekiel Elliott joined them on the All-Pro team, rampaging for a league-leading 1,631 yards and 15 rushing touchdowns while running for 91 first downs -- 19 more than anyone else in the sport.

And then there was the Cowboys' work in pass protection. Despite having then-rookie quarterback Dak Prescott under center last year, only six teams have allowed sacks and hits at a lower rate than the Cowboys since the start of last season.

In fact, the Cowboys are the only team to rank in the league's top quarter in sack rate, quarterback-hit rate, yardage per carry and percentage of runs to gain first downs since the start of the 2016 season.

The eye test, the film and the spreadsheets all come to the same conclusion: Dallas' offensive line is one of the best in recent NFL history.

"This is the best offensive line in football," Head Coach Vance Joseph said.

Even after the free-agent departure of Ron Leary to the Broncos, it hasn't missed a step, as Prescott was hit just three times in 40 pass plays during last Sunday's win over the New York Giants, including one sack. Those numbers are right in line with their rate of one sack allowed every 34.9 pass plays and one hit permitted every 14.0 pass plays the last two seasons.

"It's going to be a challenge for us," Joseph said. "They're big. They're athletic, and very, very smart."

Smart, big, and athletic, yes -- but not infallible. Not against a pass rush like the Broncos possess, and not against a strengthened defensive line that held the Chargers to just 2.91 yards per carry -- over a full yard below what the Chargers averaged in two games against the Broncos last year (4.04).

The Broncos have done their part to get ready for challenges like this one. They fortified their defensive line, asking their returning linemen to add 10 to 20 pounds in the weight room during the offseason. Nose tackle Domata Peko Sr. arrived as a free agent and has done exactly what the team expected; he's drawn the attention of offensive linemen and freed others in the front seven to make plays.

Zach Kerr and Jared Crick could return; if they do, the defensive-line rotation is at full strength. Adam Gotsis has improved in his second year and made five tackles Monday night -- two of them resulting in stops at the line of scrimmage, with another holding Chargers running back Melvin Gordon to a 1-yard gain.

"[The Cowboys'] strengths are our strengths," outside linebacker Shaquil Barrett said. "We've got a great defense, and they've got a great offense. We want to compete against the best."

Dallas' line has become the best not through anything fancy, but through simplicity and overpowering their foes. Opponents know what the Cowboys will try to do. It's just that they do it exceptionally well.

"It's not a complicated offense to prepare for or defend," Joseph said. "But they're so good at what they do, so it will be challenging."