The 2016 AFC Championship game was dubbed 'Brady vs. Manning,' but it was really a showcase of two stellar defenses.

So in a game with a bevy of storylines (Tom Brady's Deflate-gate revenge, Peyton Manning's swan song among others), the Broncos played tough, smart and adaptive football to thwart the slight underdog Patriots 20-18 Sunday afternoon.

Brady and New England had one last chance, just inside two minutes and needing a touchdown and two-point conversion to force overtime. And like he has time and time again, the quarterback found Rob Gronkowski for a huge 40-yard fourth down connection to set New England up with a first and goal at the 10 with a minute to go.

After three failures to get into the end zone, Brady found Gronk to cut things to 20-18 in the back of the end zone. Their entire season came down to the two-point conversion, which was picked off by Bradley Roby. And that was it.

The Broncos will advance to the Super Bowl where they will face the NFC Champion in two weeks.

While Pats fans lick their wounds and think about what might have been, football fans have these three observations to ponder while we await one final NFL game before the 2016 season becomes a memory.

Mixed bag for Patriots

With six minutes remaining in the fourth quarter, down by eight, the Pats and coach Bill Belichick faced a key fourth and one deep in Denver territory. And did what Belichick does -- he went for it. But the Broncos defense was ready for a quick pass to Julian Edelman, and stopped the receiver short of the marker.

The Pats 'D' forced a three-and-out and had another chance, once again facing a fourth down in the red zone. On fourth and six, a hurried Brady threw the football out of the back of the end zone, once again giving Denver a chance to ice the game.

Belichick may have made the best play of the first half himself, successfully challenging a backward pass to give New England possession close to the red zone, setting up a swift and efficient two play scoring drive capped off with Stephen Jackson's one-yard touchdown run. However, a sliced Stephen Gostkowski extra point kept Denver in the lead (it was the first missed XP of the kickers career and wound up costing New England a trip to overtime).

Gostkowski did convert a field goal in the second quarter, capping off a 14-play drive for the Patriots that was kept alive by a clutch Brady third-down scramble. Another three points came on the Pats' first possession in the third quarter, cutting the Broncos lead to 17-12.

Relentless Denver D

Brady (27-f0r-56, 310 yards, one touchdown) held the ball too long. He was picked off twice. Check for the Broncos secondary. He was also hurried constantly, and sacked four times. Check for the Broncos pass rush. The Patriots typically potent offensive attack was held in check by the Denver defense.

In the second quarter, Von Miller fooled Brady making a big interception. Manning found Daniels for a second time on a stop and go in the right-corner of the end zone, putting Denver up 14-6.

A ferocious hit on Brady during a late-second-quarter reception led to his second big mistake, Denver's second pick, this one by Darian Stewart. Though the turnover did not directly yield points, the Broncos were able to salvage enough field position to add a field goal (a 52-yarder off the foot of McManus) to put the Broncos up 17-9 after 30 minutes.

Miller was the first player to sack and intercept Brady in a postseason game.

Broncos can move the ball

After getting off the field on defense to start things off, the Broncos picked up several first downs on their opening drive, leading to a 21-yard Manning-to-Owen Daniels strike to put Denver up 7-0 early.

Manning took advantage of a seemingly disoriented New England defense on the play, resembling the Hall-of-Fame quarterback and instead of an aging superstar nearing retirement.​

In addition to a revitalized Manning (who threw for 176 yards on 17-for-32, with two touchdowns), the Broncos got a lift from their running game early in the fourth quarter after it lie dormant for most of the game when C.J. Anderson broke loose for a 30-yard gain on a third and one. Though Manning wasn't able to hook up with Jordan Norwood in the end zone for six, Brandon McManus added three to give Denver a big eight-point edge.