The Kansas City Chiefs gave a rough send-off for the retiring Ben Roethlisberger as they emerged with a 42-21 win over the Pittsburgh Steelers. A slow start initially marred Patrick Mahomes and the team but they eventually bounced back and took control of the game to secure the first-round victory.

Andy Reid's squad can surely look back and learn a lot from this game as they continuously work on improving themselves in preparation for the remainder of their postseason campaign. After Sunday night's victory, the Chiefs will now be slated in a highly-anticipated rematch against the Buffalo Bills in the AFC Divisional Round next weekend.With that said, here are three takeaways from the Chiefs' Wild Card Round victory over the Steelers:

3. Kansas City's defense showed up and had a solid outing.

In Week 18 against the Denver Broncos, the Chiefs' defense had a sloppy performance which ultimately allowed their opponents to come close in dealing them an upset victory. Though they still managed to win, it was evident that their defensive efforts would need some work after that game.

Against the Steelers, defensive coordinator Steve Spagnuolo and his men came out with an improved performance to limit the scoring of Roethlisberger and company. Cornerback L'Jarius Sneed made his presence felt in the secondary as he came out with six solo tackles and two assists. Defensive linemen in Mike Danna and Tershawn Wharton also made life hard for the Steelers QB as they both recorded a sack each against him.

Sure, there were still some lapses that they need to work on, but their overall performance was enough to maintain a comfortable lead against the Steelers until the end. After getting the win, the Chiefs' defense will have to be even better as they aim to contain a more dynamic Bills' offense in the next round of the playoffs.

2. Jerick McKinnon finally broke out for the Chiefs.

Veteran running back Jerick McKinnon only saw limited action for Kansas City as he was haunted by several injuries throughout this season. With Clyde Edwards-Helaire still sidelined and Darrel Williams playing through a toe injury, the 29-year-old was finally given a chance to contribute and prove his worth to the team.

McKinnon made the most out of the opportunity as he showed his ability to be a dual-threat on the field. He led the ground game and ran 61 yards on 12 carries while also contributing in the passing game with 81 yards on six receptions and a touchdown.

His recent performance against the Steelers highly spoke of his ability to be a reliable talent who can come out with timely contributions when needed. Given the current situation of the Chiefs' backfield, the Georgia native may just find himself getting involved in more snaps and receiving a more sizable role for their upcoming games.

1. Patrick Mahomes was sensational in leading the offensive attack against the Steelers. 

Quarterback Patrick Mahomes found himself going through a rough patch as he recorded an interception early in the game. He picked himself up and stepped on the gas pedal as he seemingly gained momentum in orchestrating the team's offense.

The former league MVP threw with accuracy as he located his weapons in the endzone. McKinnon, along with Travis Kelce, Tyreek Hill, Byron Pringle, and Nick Allegretti were beneficiaries as they all contributed to the scoring department for the Chiefs.

Mahomes ended the night with a total of 404 yards on 30-of-39 attempts and five touchdowns. Surely enough, the Chiefs wouldn't have been able to overcome their slow start if it wasn't for the stellar bounce-back performance of their star quarterback.

He will continue to be at the forefront of their attack as they aim to replicate the same success of the offense in their upcoming Divisional Round matchup against the Bills next week.