The Chiefs defense gave up 500 yards to the Patriots on Sunday night, including 173 on the ground. But with 5:33 to go in the fourth quarter and Kansas City leading, 33-30, it was these four yards that may have been the difference between the Chiefs moving to 6-0 or dropping their first game of the season:

That's 41-year-old Tom Brady somehow avoiding a sack from rookie linebacker Breeland Speaks, and then diving into the end zone for the go-ahead touchdown.

There were 16 points still to be scored in one of the most exciting games of the season, but you have to wonder if things would have been different if Speaks didn't let go of Brady. Which brings us to this: why did Speaks let go of Brady?

Turns out, Speaks, who has a sack and forced fumble on the season, was concerned about being flagged for roughing the passer.

"It was definitely on my mind," he said after the game, via NFL Network's Michael Giardi, adding: "It sucks."

Speaks said he thought Brady had already thrown the ball (in the clip above you can see Brady pump fake before breaking for the end zone) and he thought bringing down the Hall of Famer was a recipe for a penalty flag.

"Especially in New England," Speaks said, via the Kansas City Star's Sam Mellinger. "We're in New England. Tom's going to get the call."

We'll never know but it didn't matter anyway; the Chiefs were flagged for defensive holding in the end zone and even if Speaks had sacked Brady, the Patriots would've earned a first-and-goal as a result of the penalty.

So what's the bigger takeaway for the Chiefs? A year ago, they headed into Week 6 with a 5-0 record as one of the league's best teams. By Week 13, they were 6-6 before getting hot down the stretch only to lose to the Titans in the wild-card round. But this team, which was 5-0 until Sunday night's loss to the Patriots, seems better equipped to rebound from a setback.

"It's a bittersweet, moral victory for us," Speaks told Yahoo.com. "We know what we've got to work on, we know we've got to stop the run. But I feel like we're definitely going to see them again."

That was a familiar refrain in the Chiefs locker room, partly because this offense is playing with a lot of confidence but also because the defense, which has been exposed this season, will improve with the return of Justin Houston and Eric Berry.

"Our leaders aren't out there," linebacker Reggie Ragland explained to Mellinger. "Pro Bowlers. We ain't got them out there. When we do get them out there, we'll be so much better."