There have been ups and downs for the Kansas City Chiefs defense through the first nine weeks of the season. Overall, the group ranks 19thin the league by allowing an average of 23.1 points per game.

But it's also a group that's been tested—having faced four of the league's top seven offenses already this season in the Eagles (No. 2, 31.4 ppg), Texans (No. 3, 28.6 ppg), Cowboys (No. 4, 28.3 ppg) and Patriots (No. 7, 27.0 ppg).

The Chiefs held three of those four teams to below their season averages in terms of points, but they've also allowed an average of 390.3 yards per game, which ranks 29th in the league.

In the final seven games of the regular season, the Chiefs defense won't face a team that's currently ranked higher than 15th in the league in terms of average points per game, and that offense that's ranked 15th is the Oakland Raiders, who have to come to Arrowhead Stadium.

At home, the Chiefs' defense has allowed an average of just 19.5 points per game, compared to the 26 points per game they've allowed in the five road contests this year.

Basically, here's to hoping for more plays like the ones listed below, which all came in wins.

Here are five defensive plays to remember through the first nine games of the year:

1. The key fourth-down stop early against the Patriots

After the fumble from rookie running back Kareem Hunt on the very first carry of his career in Week 1 against the New England Patriots, the Chiefs' defense was quickly put to the test.

Already trailing 7-0 and with the Patriots getting the ball at the Chiefs' 32-yard line, the defense had to step up to keep this game close early in the first quarter.

Hunt said after the game that some of the defensive players came over to him after the fumble and told him they'd pick him up, and they did.

On a third-down pass across the middle to Danny Amendola, veteran safety Ron Parker came up and made a great open-field tackle to keep Amendola short of the first down.

Parker, who was actually questionable coming into that game with an ankle injury, finished with a team-high 11 tackles on the night. And it was his tackle that set up a fourth-and-short for the Patriots' offense, which decided to go for it rather than taking the short field goal.

On the fourth-down attempt, defensive lineman Bennie Logan, safety Eric Berry and company helped stuff the run up the middle. It was a momentum-changing play that really changed that entire game. It looked to settle down the Chiefs after a first five minutes that completely went the Patriots' way.

The Chiefs went on to win in decisive fashion, 42-27.

2. Chris Jones has the game of his life against the Eagles

There's no denying that Jones had a fantastic rookie season, finishing as a Pro Football Focus darling and routinely causing havoc up front as he worked his way into the defensive rotation.

But he never had a day like he did against the Eagles in Week 2. 

Jones finished the game with three sacks and an interception—displaying an inability to be contained in a game in which he needed to step up, as did everyone, with All-Pro safety Eric Berry being out after his season-ending injury late in the game against the Patriots.

On the interception play, which was by far the most memorable from that game, linebacker Justin Houston was able to get a hand on the ball and deflect it into the air and right into the hands of Jones, who secured the ball for the interception.

It set up the Chiefs' go-ahead touchdown just a few plays later, which proved to be the game-winner against an Eagles team that hasn't lost since that day.

3. Marcus Peters did what Marcus Peters does against the Chargers

In Week 1, the New England Patriots' Tom Brady targeted Peters—the All-Pro cornerback—just once, and then in Week 2, Eagles' quarterback Carson Wentz threw it at Peters seven times.

Going into the game against the Los Angeles Chargers in Week 3, the matchup between Peters and Chargers' receiver Keenan Allen was one to watch, as was how much Peters would be targeted in general.

And the first time Rivers threw in Peters' direction, he made him pay.

Midway through the first quarter, Rivers attempted a deep out-route in Peters' direction, and he stepped in front of it and took it 38 yards in the other way to set up the Chiefs second touchdown of the day.

At the time, it was the first interception for Peters on the season and the NFL-leading 15th interception for him since he entered the league in 2015.

Since that game, Peters has picked off two more passes.

4. Justin Houston's touchdown to close out win over Redskins

In Week 4 against the Washington Redskins, the game will be remembered by many as the game that rookie kicker Harrison Butler hit the game-winner in his NFL debut, which came on national television on Monday Night Football.

But the game actually ended with a Justin Houston 13-yard fumble return for a touchdown as the Redskins tried a last-ditch attempt to make something happen as time expired.

It wasn't going to matter, but Houston's play was definitely an exclamation point on a huge win for the Chiefs against the Redskins in Week 4.

5. Peters just stole it away from Jamaal Charles

Less than six minutes into the game in Week 8 against the Denver Broncos, Peters simply took the ball away from Broncos' running back Jamaal Charles, who was making his return to Arrowhead Stadium.

It's not the first time we've seen Peters just take the ball away from someone either.

Last year against Carolina Panthers' receiver Kelvin Benjamin, Peters did something similar late in the game, but this time, he picked it up and raced 45 yards the other way for the touchdown—beginning a barrage of big defensive plays for the Chiefs on the night.

The play gave the Chiefs an early 7-0 lead, and they would never trail in the game.

They finished the game with five takeaways, which is a season-high.