ENGLEWOOD, Colo. -- It has become a source of pride for the Denver Broncos, their football signature in recent seasons.

And while the team’s defense still has a chance to close out the Broncos' troubled 2017 season as the league’s No. 1 overall with a lock-down performance against the Kansas City Chiefs in Sunday’s season finale (they're No. 2 going into the game), at 5-10, the current state of affairs doesn't feel that good.

“We didn’t win this year, so you can’t really call it a championship defense," Broncos linebacker Von Miller said. “We’d still be living in the past if I say we’re still a championship defense. We’re still a really good defense that can win championships. Yes, we do have that -- we’ve just got to build on that."

It’s been quite the run given this likely will be the fifth time in the past six seasons the Broncos have finished among the league’s top four in total defense. The pinnacle to this point, of course, was the 2015 season when the Broncos were No. 1 overall, No. 4 in scoring defense, No. 1 in pass defense and No. 3 in run defense.

That defense powered a Super Bowl 50 win, and this year’s squad -- they believed when they adjourned training camp -- was supposed to do the same.

But there are two rather glaring numbers that have overwhelmed the rest. The Broncos have surrendered 135 points after turnovers this season -- that’s nine points per game or 4.35 points per turnover -- and they also have surrendered 29 touchdown passes this season, bettering only the New York Giants (32) in that category.

The 135 points off turnovers is certainly a result of just how many times the Broncos have turned the ball over on offense and special teams this season to put their defense back on the field in the “sudden change" situations, often not in the best of circumstances. But the Broncos haven't held their ground enough, either, as they have seven games this season in which they’ve surrendered at least 13 points off turnovers, and the only two games the defense didn’t surrender points off turnovers were also the only two games the Broncos didn’t commit one.

“It’s been a little crazy," said cornerback Chris Harris Jr. "Those are situations we've handled in the past and we have at times this season, but not enough, probably."

The touchdown passes given up, for a defense that finished both 2015 and 2016 No. 1 against the pass, has been an unexpected and consistent problem this season. This past Sunday Washington Redskins quarterback Kirk Cousins became the fifth different quarterback to throw at least three touchdown passes in a game against the Broncos this season.

Philadelphia’s Carson Wentz had four touchdown passes in the Eagles’ win over the Broncos last month, and Cincinnati’s Andy Dalton had his three touchdown passes in just 15 completions.

“[Offenses] have things they do to make us work," defensive coordinator Joe Woods said. “We’ve just had some miscommunication. ... It’s just part of football."

Woods, who was promoted to replace Wade Phillips as the defensive playcaller shortly after Vance Joseph was hired as Broncos head coach, has tweaked some things in the defense, and the Broncos have done some things in coverage they had not under Phillips.

They have shown more zone looks, as opposed to man-to-man, in some down-and-distance situations they had not in the previous two years. And at times it has resulted in Broncos defenders looking at each other following scoring plays, including on Sunday when Harris and Aqib Talib, two players who have been to multiple Pro Bowls, were exchanging words following one of Cousins’ touchdown throws.

“Our main focus this year, we kind of changed our philosophy -- our main focus was not to give up any [rushing touchdowns], that kind of put a lot of guys [in position] to get thrown at in the red zone," Harris said. “That was our philosophy, no rushing touchdowns, and that’s why the numbers are up."

Opposing offenses also have taken great care to use formations and players in motion to often get cornerback Bradley Roby or safety Will Parks isolated in coverage, as quarterbacks have often chosen to avoid Talib and Harris in those situations. And then consider the Broncos’ offensive woes, which have played a role in them trailing at halftime in nine of their 15 games and trailing at the end of the third quarter 10 times, forcing the Broncos to take more chances on defense in those games.

“That’s some of it, and in some spots, I would say, especially early in the season, we blew some coverages," Joseph said. “So we gave up some big plays. I think from the middle of the season to the end it’s been more of that, being aggressive, trying to get back in the football game."