KANSAS CITY, Mo. – The Kansas City Chiefs’ wait to return to the Super Bowl had already stretched 49 years.

Now they’ll wait at least 50.

Credit a Bill Belichick game plan for New England that the Chiefs defense couldn’t get off the field the first half, followed by a Chiefs offense that uncharacteristically couldn’t stay on until the third quarter. An exciting second half of five lead changes, Patrick Mahomes bombs and replay after replay sent the contest to overtime.

But the Chiefs couldn’t hold off the playoff-legend Belichick and Tom Brady. Brady engineered a 13-play, 75-yard drive to set up Rex Burkhead for the 2-yard game-winning touchdown.

Mahomes’ magical first season as a starter comes to an end as Brady and Belichick pack for their ninth Super Bowl career appearance, this time against Sean McVay’s Los Angeles Rams in Atlanta.

Here are three things we learned in the Patriots’ 37-31 overtime win:

1. Belichick knows how to game plan: This wasn’t the New England team that crushed the Colts for 35 points in the first half of a runaway divisional game. But while the Patriots only led by seven points until 33 seconds remained in the second quarter, their 245 first-half yards to the Chiefs’ 32 and 21:07 time of possession to Kansas City’s 8:53 felt far more lopsided. The Patriots capitalized time and again on a Chiefs run defense that allowed 132.1 yards a game this season (27th), giving lead back Sony Michel 29 carries, which he took for 113 yards and two scores. Even when Chiefs linebacker Reggie Ragland intercepted Brady in the second quarter, the Chiefs offense sputtered for a three-and-out. They went into halftime scoreless.

2. But the Chiefs answered: Mahomes completed three consecutive passes for 71 yards on the first drive of the third quarter to score in just two minutes after failing to do so for 30. Kansas City would score two more touchdowns before the Patriots’ next (New England kicker Stephen Gostkowski was, however, good for a 47-yard field goal in between). Six lead changes sparked a game full of replays and close calls. Mahomes showcased some of his electric throws throughout the day, including back-to-back second-quarter plays, first with a dart to Sammy Watkins as Patriots safety Devin McCourty wrapped his ankles and then with a 42-yard bomb to Tyreek Hill. In the second half, he finally strung together enough big-time plays – and a side-arm baseball throw to Watkins that must’ve made Pat Mahomes Sr. proud – to score. Each time New England rushed for a touchdown in the second half, Mahomes marched his team back down to score.

3. Your point is? Julian Edelman’s touch became the subject of a key fourth quarter moment when the Patriots wide receiver's fingers appeared to graze a punt return that the Chiefs' Gehrig Dieter recovered. Officials granted the touchdown before the play went to review, a montage of Edelman’s thumb and forefinger placement during the bounce on repeat at Arrowhead. Ultimately, the call was overturned. No sweat. Just three hours after the Saints’ fury at a no-call pass interference that Rams cornerback Nickell Robey-Coleman even declared such, the Chiefs stayed locked in and picked off Brady two plays later. Daniel Sorensen returned the interception 24 yards to set up a Chiefs’ go-ahead score. But it wasn't enough in the end.

Follow Jori Epstein on Twitter @JoriEpstein.