LONDON — The Broncos have perhaps the best defense in the NFL, and Zach Allen figures it can be even better.

Consider inside linebacker Dre Greenlaw, a stalwart the past six seasons with San Francisco, has yet to play this season due to a quad injury. He is now eligible to come off injured reserve, but it remains uncertain when he will return.

Also consider that defensive tackle Malcolm Roach is still getting back in the groove after missing the first five games due to a calf injury. He played 25 of a possible 57 defensive snaps in his season debut in Denver’s defensive masterpiece Sunday, a 13-11 win over the New York Jets at London’s Tottenham Hotspur Stadium.

“It’s going to be pretty crazy,’’ Allen, a defensive lineman, said after the game about how much better Broncos’ defense could be at full strength. “You saw a little bit of it obviously with Roach (back).”

The Broncos sacked Jets quarterback Justin Fields nine times, tying a team record for the most in a game. The sacks were split among eight players, showing the tremendous versatility of Denver’s defense.

“It’s a really special thing,’’ said Allen, who shared in two sacks. “And the fact that it was spread across everybody is cool. That’s pretty rare.”

The Broncos, who next play at home Sunday against the New York Giants, lead the NFL with 30 sacks, 10 more than any other team. They are No. 2 in the league in both total defense and scoring defense.

The Broncos are giving up 254.2 yards per game, just behind Atlanta’s average of 253.4. They are allowing 15.8 points per game, trailing only Houston, which is giving up 12.1. The Broncos play at Houston on Nov. 2, which could be quite the defensive struggle.

The Broncos have bounced back in a big way after they gave up 473 yards in a 29-28 loss in Week 2 at Indianapolis and 376 in a 23-20 loss at the Los Angeles Chargers in Week 3. In the last three games, a 28-3 win over Cincinnati in Week 4, a 21-17 win at Philadelphia in Week 5, and Sunday’s victory over the Jets, they’ve allowed an average of just 10.3 points and 181 yards.

“We’ve been in that groove, just a relentless groove,’’ said nose tackle D.J. Jones. “It’s special to be a part of it.”

The Broncos allowed the Jets a meager 82 yards of total offense. Taking into account the sacks, the Jets had minus-10 team passing yards, the fewest allowed in Denver history and the second-fewest given up by an NFL team since 1990. The San Diego Chargers had minus-19 in a 1998 game against Kansas City.

“I was shocked when they told us after the game,’’ Broncos outside linebacker Nik Bonitto about the Jets’ minus-10 number. “That’s pretty funny.”

Bonitto shared in two sacks against the Jets to raise his NFL-leading total to eight. Bonitto, who recently told The Denver Gazette it is “very reasonable” to break Von Miller’s team record of 18.5 sacks in a season set in 2012, is on pace to shatter that mark. In fact, at his current pace, he would slightly better the NFL record of sacks in a season of 22.5.

Can you say NFL Defensive Player of the Year?

“It’s a long season,’’ Bonitto said of the possibility of winning it. “I have a lot of room to grow in my game and keep playing and stack wins. I have a long way to go before we start having those conversations.”

Last year’s Defensive Player of the Year, cornerback Pat Surtain II, has called Bonitto the leading candidate to succeed him for the award. On Sunday, Surtain relished seeing the the Broncos pass rushers swarm Fields.

“It was honestly pretty crazy,’’ Surtain said. “It was just like I was sitting back watching, being a fan of it, you know what I mean, because we’re covering. It’s barely 1 or 2 seconds, I look up, there’s a sack. So it’s a pleasure to watch and a pleasure to be part of.”

The Broncos’ offensive players sure liked watching the show from the sideline. The defense on Sunday bailed out an offense that managed just 246 yards, including just 71 in the second half

“They’ve been playing their butts off week in and week out,’’ wide receiver Courtland Sutton said of the defense. “It’s been a special thing to be able to watch and I’m just grateful to be able to be on a team with guys that are playing at the level that they’re playing at. They’re out there playing at a mindset that they feel that nobody can stop them . … The sky’s the limit for them and I’m grateful for them.”

As good as the Broncos defense has been lately, it could be even better if it gets back to full strength.