The A.F.C. side of the playoffs have concluded the same way for four seasons running, with the conference’s second-best team traveling to play the Kansas City Chiefs at Arrowhead Stadium. Their opponent this time is the Cincinnati Bengals, who defeated Kansas City in Week 17 on a field goal as time expired, dislodging it from the A.F.C.’s top seed.

The rematch carries weightier consequences. The Bengals haven’t played in a Super Bowl in 33 years, and Kansas City, after going 50 years between appearances, is aiming for its third straight.

Patrick Mahomes on Sunday will become the first quarterback in league history to start four conference championship games before his 27th birthday. He overcame an uneven stretch earlier this season by staying patient, and last week against Buffalo in the divisional round threw for 378 yards without attempting even one pass of 20 or more yards. Mahomes relies on a fleet of receivers to gain yards after the catch, and his two favorite targets are tight end Travis Kelce, who has 13 receptions for 204 yards this postseason, and Tyreek Hill, who has grabbed 16 passes for 207.

Mahomes threw for 259 yards and two touchdowns in Week 17, but Kansas City blew three separate 14-point leads because their defense couldn’t thwart Cincinnati’s duo of Joe Burrow and Ja’Marr Chase, who accounted for 266 receiving yards and three touchdowns.

Kansas City’s defensive coordinator, Steve Spagnuolo, probably won’t deploy as much press coverage as in that last meeting. The likely return of safety Tyrann Mathieu, who missed much of the Buffalo game with a concussion, could also help, as would another disruptive game from defensive lineman Chris Jones. The Titans sacked Burrow nine times in the divisional round, and if Jones, an interior force, can generate consistent pressure, he may help determine the outcome of Sunday’s game.

In the second year of his N.F.L. career, Burrow rejuvenated a middling Cincinnati franchise that hadn’t won a playoff game since before he was born.

Burrow showed he had the potential to be the Bengals’ quarterback of the future during his rookie season, when he threw for over 300 yards in five of the 10 games he started, but his season was cut short after he tore multiple ligaments in his left knee against Washington in Week 11 last season.

Burrow returned from injury this season and dazzled with his ability to throw accurate downfield passes into tight windows under tremendous pressure. Although Cincinnati surrounded Burrow with talented offensive pieces — including Chase, Burrow’s former Louisiana State teammate and this season’s Offensive Rookie of the Year Award-winner — the Bengals have made few improvements along their struggling offensive line. Burrow was the most sacked quarterback (51) during the regular season.

In the Bengals’ 3-point win over the A.F.C.’s top-seeded Titans in the divisional round, Burrow spent much time either on the ground or scampering away from Tennessee’s defensive front. The Titans recorded 13 quarterback hits on Burrow and sacked him nine times, which tied a postseason record.

Although the Bengals were able to eke out a 19-16 victory against Tennessee, it’s rare that a team which allows its quarterback to face such pressure can continue to win. Cincinnati’s ability to provide Burrow with a clean pocket against Kansas City’s pass rush will be a deciding factor in the Bengals’ offensive success.

The Bengals had no trouble scoring points during the season, though, and could likely keep pace with Kansas City’s high-powered offense, which has scored 42 points in each of the first two rounds of the postseason. Cincinnati had a top-10 scoring offense behind Burrow, Chase and running back Joe Mixon, who had 1,205 rushing yards and 13 touchdowns, both career highs, during the regular season.

Although most of the Bengals’ success has been predicated on Burrow’s connection with his playmakers, they’ve gotten help from their defense, especially lately, in closing out games.

In Cincinnati’s win over the Raiders in the wild-card round, linebacker Germaine Pratt snagged an interception on Las Vegas’s potential game-tying drive to seal the game. And against the Titans, linebacker Logan Wilson intercepted Ryan Tannehill with 20 seconds left in the game to set up Evan McPherson’s game winning 52-yard field goal.

Vonn Bell, a safety and captain on the Bengals’ defense, told reporters this week that having faced Mahomes and Kansas City recently helps, adding that Cincinnati’s defensive unit needs to “clean up our technique” in the conference title game.