FOXBORO -- The Patriots defense smothered the Chiefs in the second half Sunday afternoon. They allowed Patrick Mahomes to throw for just 57 yards on 15 attempts. They allowed 97 yards total and five first downs on five possessions.
That might read like a winning effort. But the Patriots allowed 20 points in the first half. And with their offense finding points hard to come by right now, that was enough to get them beat, 23-16. The margin for error for Bill Belichick's defense, going up against last year's MVP, was wafer-thin.
"We trust our offense," Duron Harmon said after the game. "We know eventually they're going to get it going, and they got it going in the second half. They made a lot of plays. We just gotta make sure we don't give up touchdowns. Can't give up the big plays, just play a complementary football game.
"We're all leaning on each other. They're leaning on us. We're leaning on them. We're all leaning on the special teams game. When we play complementary football between all three phases that's when we're at our best."
That complementary game was lacking in the first half for the Patriots. First, the offense couldn't pick up the defense when they were gifted good field position. JC Jackson's first-quarter interception gave the Patriots the ball at the Kansas City 40-yard line with a chance to go up 14-0. The result: loss of one; incomplete; incomplete; punt.
Later, special teams couldn't pick up the defense. A blocked field goal gave the Chiefs good field position late in the first quarter, which was followed by a 48-yard touchdown to rookie wideout Mecole Hardman.
"I saw with the coverage they were kind of doing that thing where they were trying to put an extra guy with Tyreek [HIll]," Patrick Mahomes said. "I knew if Mecole – with his route, if he could get the guy to kind of go underneath him, then he was going to be able to break out and be open.
"Obviously they had I think a five-man rush and so the guys were getting a little bit of pressure on me, so I tried to buy an extra tick, put the ball out there. I didn't want to overthrow him so I kind of threw it a little shorter where he could adjust, because I knew he was going to be open. With that guy, if you get the ball in his hands, he can make plays happen and you saw that."
From there it looked like the Patriots played more two-high safety coverages in order to guard against explosive plays. They were willing to open up space for the Chiefs to hit them with underneath passes in order to prevent The Big One and they succeeded.
The only other touchdown drive the Patriots allowed came when bad complementary football struck again. Tom Brady's interception early in the second quarter gave the Chiefs the football at the Patriots 35-yard line. They were in the end zone seven plays later when Travis Kelce took a direct snap and ran it into the end zone.
"We gave up the one long play," Devin McCourty said. "Against that offense you can't give it to them in one play. Then we had them in the red area and then we gave it up on the Wildcat triple-option. So, it was really two bad plays in the first half and I thought we just did a better job of eliminating that.
"When you play a good team, you can't have those plays. I thought in the second half we really locked in and just did a better job of not giving up the big play or a silly play in a key situation. Third down in the red area, we've got to play our best football."
Had the Patriots been able to muster a more effective offensive attack, though, they might've been able to withstand one or two letdowns defensively. Tough sledding wouldn't begin to describe what they went through for portions of the afternoon on that side of the ball.
The offense converted on just 3 of 15 third and fourth-down plays. They were 1-for-3 in the red zone. They were sacked three times, and Brady averaged just 4.7 yards per pass attempt. Through the first half, the Patriots picked up only 3.4 yards per carry against a defense that was allowing more than 5.0 yards per carry for the season coming into the game.
Brady's longest pass came on a 37-yard flea-flicker for a touchdown. The second-longest Patriots pass of the night came off the fingers of running back James White -- a 35-yarder in the fourth quarter to Jakobi Meyers. The Patriots pulled out all the stops, utilizing 11, 12, 20 and 22-personnel packages. They tried to run it with Sony Michel. They tried the screen game. They tried the vertical passing game. They tried to run their hurry-up attack. Very little worked.
The Patriots are running out of time to find out what they do well on offense. If it can be boiled down to taking care of the football and avoiding negative plays -- which they weren't able to do consistently Sunday -- then the defense is going to have to not only eliminate negative plays but come up scoring plays themselves.
They thought they had one of those when Stephon Gilmore scooped up a McCourty forced fumble late in the third quarter. But the play was blown dead and the Patriots had to challenge the ruling just to ensure they'd win possession. Cameras caught Belichick on the sideline gesturing emphatically to officials -- raising his arms over his head as if signaling a touchdown -- to let them know he thought they took points off the board for his team.
It's not just the defense. Pressure is on Patriots special teams units as well to come through with big plays as the offense has sputtered. They got one Sunday when Nate Ebner rushed through the middle of the Chiefs line to block a punt. That led to a two-play touchdown drive to cut the Chiefs lead to 23-13.
"It's our goal to make big plays every week," special teams captain Matthew Slater said. "You have guys on this team that are here strictly because of special teams. Myself included. We feel like we have a responsibility to go out and try to leave a mark on the game."
The Patriots very nearly had a second blocked punt later in the game -- they went without a returner to get extra heat on the Chiefs -- but Justin Bethel just missed getting his hands on the football as he penetrated the line.
"I thought I was going to get it," Bethel said. "I was there. For me, I feel like that's one of those plays I gotta make."
Those are the types of plays -- turnovers that lead to touchdowns, swatted kicks -- that other teams might view as gravy. Instead, with an offense in search of whatever help it can get, those kinds of plays might have to be the lifeblood that sustains the Patriots at times through December and into January.
"We always talk about complementary football and that's what we were thinking," McCourty said. "Defense, we've got to get them on the long field, three-and-out. Or we've got to get a turnover, get our offense a short field. When we're able to do that, they were able to put some points on the board."
Teeing up the offense like that week after week is a tall order. But until the Patriots offense finds itself -- if the Patriots offense finds itself -- they'll need the help. Without it Sunday, they might've landed in the single digits.
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Margin of error for Patriots defense thinning as offense struggles originally appeared on NBC Sports Boston