The Kansas City Chiefs (10-5) beat the Cleveland Browns (3-12) by a score of 17-13 Sunday afternoon at Arrowhead Stadium.

Here are 10 observations from the game:

1. The Chiefs have made the playoffs!

It wasn't easy, but the job got done on Sunday.

With their 17-13 win over the Browns and a subsequent loss by the Pittsburgh Steelers, the Chiefs have earned a playoff berth after starting the season with a 1-5 record.

Simply unbelievable.

Without Pro Bowl linebackers Justin Houston and Tamba Hali, who were out with injuries, the Chiefs defense was still able to stand tall and keep Johnny Manziel and the Browns offense out of the end zone when it mattered the most.

This game showed everything of what this season has been about for the Chiefs—adversity, pressure and guys stepping up when their name was called.

The win on Sunday also gave the Chiefs their ninth consecutive victory, which ties a franchise record (2003, 2013).

2. Defense stands tall in the fourth quarter

They were defensive stands that were needed to win the game, and the Chiefs came through.

Leading by just a touchdown, the Chiefs defense was tasked with keeping the Browns offense out of the end zone after it had driven down inside of the red zone midway through the fourth quarter.

They key play on the first attempt was a second-down pass from Johnny Manziel at the 8-yard line, in which the defensive pressure forced him to throw earlier than he wanted. The problem was he threw the ball to his right tackle, Mitchell Schwartz.

The play resulted in two penalties, illegal touching by Schwartz and also intentional grounding by Manziel, as the pass didn't get back to the line of scrimmage.

Rather than a goal-to-go situation on third down, the Browns then faced a third-and-goal from the 18-yard line after the 10-yard penalty and loss of down.

The third-down pass fell incomplete and the Browns had to settle for a field goal, cutting the Chiefs lead to 17-13.

On their next offensive drive, the Browns faced a fourth-and-7 from the Chiefs 30-yard line, and the pass once again fell incomplete.

They were given another opportunity, and on fourth-and-10 from the Chiefs 32-yard line with 15 seconds left to play, the pass was completed, but the clock ran out before they could get off another play.

And with that, the Chiefs won their ninth straight.

3. Alex Smith finds success through the air and on the ground

Alex Smith finished the first half 11 of 17 for 89 yards with 2 touchdowns and just 1 interception.

Midway through the third quarter and on a first-and-10 play from midfield, Smith hit receiver Albert Wilson for a gain of 19 yards, which broke Smith's previous career high in yards passing (3,313, 2013) in a season.

He had touchdown strikes to Jeremy Maclin for 11 yards and Travis Kelce for 13 yards, but the 6 rushes he had for 54 yards may have been the difference for the Chiefs in the first half, and they took a 17-3 lead to the locker room.

With those runs, Smith also broke his own franchise record for yards rushing in a season by a Chiefs quarterback, which was previously 413 yards set back in 2013.

4. Marcus Peters (unsurprisingly at this point) does it again

He continues to make his case as the NFL's Defensive Rookie of the Year.

On second-and-9 from the Chiefs 40-yard line, Peters undercut a crossing pattern from Gary Barnidge and the pass from Johnny Manziel went right into the hands of Peters, who returned it 46 yards the other way.

It was Peters' 8th interception of the season, which is not only a team high, but it also ties him for the franchise record for picks in a season by a rookie (Bobby Hunt, 1962).

Peters was named to the Pro Bowl earlier this week. He's the first defensive back for the Chiefs to be named to the Pro Bowl since Eric Berry (2010).

5. Andy Reid challenges a key play and wins

On the third Browns offensive drive of the game, Johnny Manziel scrambled on third-and-4 from the Chiefs 23-yard line and tried to pitch it back to Duke Johnson Jr. after crossing the line of scrimmage.

When the play happened, it looked like a legal lateral that was pitched backwards to Johnson, and it resulted in a first down very reminiscent of the kind of play that gave him the "Johnny Football" nickname. But Andy Reid thought otherwise and challenged the play.

After review, the refs agreed with Reid and the play was not only overturned, but a flag was thrown. The result was a field goal by the Browns rather than a first down run inside of the red zone.

After the field goal, the Chiefs held a 10-3 lead midway through the second quarter.

6. Chiefs get out to a fast start

The Chiefs started the game off right by going 65 yards on 11 plays in 7:08 on an opening drive that culminated with an 11-yard touchdown pass from quarterback Smith to Maclin.

The drive continued thanks to 2 third down conversions on the drive, one of which was a 6-yard scramble by Smith on third-and-3. Smith's ability to pick up yards with his legs has been one of the real strengths of the Chiefs offense over the past few weeks.

Smith had 2 runs for 12 yards on that first drive.

7. Jeremy Maclin goes over 1,000 yards for the season

Maclin needed just 15 yards coming into Sunday's game to surpass the 1,000-yard mark for the season. After a 14-yard hookup between Smith and Maclin on the first play of the game, Smith once again found Maclin on a post route inside the red zone.

Similar to their hookup last week against the Baltimore Ravens, Maclin was able to get inside of the defender and Smith made a perfect pass across the middle to give Maclin an opportunity for a diving touchdown catch.

The 11-yard hookup gave Maclin 1,000 yards receiving for the second time in his career (2014).

8. Chiefs defense continues to stand tall in short-yardage situations

The Chiefs came into Sunday's game as the best defense in the NFL in third-and-1 and fourth-and-1 situations, allowing conversions just 43.5 percent of the time.

The NFL average is 63.5 percent.

On the second Browns offensive possession of the game, they faced a third-and-short from midfield, and Derrick Johnson and company stuffed the Duke Johnson Jr. run at the line of scrimmage.

The Browns, trailing 10-0 at the time, were forced to punt the ball back to the Chiefs.

9. Jeff Allen's fantastic block on Charcandrick West's long run

On the Chiefs second offensive drive, second-year running back Charcandrick West took a handoff to outside of the left tackle, Eric Fisher, and was able to pick up 22 yards thanks to a great block down the field by left guard Jeff Allen, who was back in the lineup after missing the last two weeks with an ankle issue.

Allen took two Browns defenders out down the field as he helped spring West towards the open field.

The 22-yard gain helped set up Cairo Santos' 40-yard field goal, which gave the Chiefs an early 10-0 lead.

10. Daniel Sorensen makes another big special teams play

He's quickly becoming a trusted playmaker for the Chiefs special teams units.

On the final play of the first half and with Cleveland trying to narrow Kansas City's 17-3 lead, the Browns field goal attempt was blocked as second-year player Daniel Sorensen broke through the line of scrimmage and got a hand on the ball.

It was the Chiefs first blocked field goal of the season.