WR Eric Decker's drive through two Chargers' defenders to a fourth-quarter touchdown epitomized the drive and determination Denver showed in its second-half comeback. (US Presswire)

If the Broncos had been graded at halftime of Monday night's comeback win over San Diego, they might have received across-the-board Fs. The 24-point hole they dug was the largest of the season as the Broncos did little right beyond running through the tunnel before the opening kickoff without tripping over themselves.

But just as semesters take three or four months, the game is 60 minutes, and the Broncos responded with not just their best half this season, but perhaps in the franchise's history, scoring a team second-half record 35 points with contributions from throughout the roster.

Offense: B+

For the first time this season, the Broncos didn't begin the game by receiving the opening kickoff. That seemed to contribute to the offense being out of sorts in the first half, one doomed by miscommunication that led to an interception, scattershot pacing and a blocking scheme that struggled to adapt. Everything changed after halftime, as Peyton Manning completed 13 consecutive passes after the break. By the time he finally misfired, Denver had turned a 24-point deficit into a 28-24 lead. Manning's second-half dominance forced the Chargers to temper their aggression and drop into zones, which opened holes for RB Willis McGahee, who averaged 6.3 yards on six fourth-quarter carries after being limited to 18 yards on 11 runs in the first three quarters. Denver's only second-half mistake was pulling off the throttle with a 28-24 lead, which led to its only second-half punt. Previous game's grade: B-

Defense: A- 

Early in the game, the Broncos couldn't generate consistent pressure and couldn't contain Chargers TE Antonio Gates, who scored both San Diego touchdowns and left the Broncos' safeties looking helpless and confused. After halftime, Von Miller and Elvis Dumervil changed the dynamics of the game, moving around the front line and attacking from all angles. The Chargers often kept an extra tight end in the backfield to block them, but it proved useless, and the edge-rushing duo finished with three of the Broncos' four sacks. It also altered Philip Rivers' throws, which led to three second-half interceptions -- one of which was returned for a touchdown. Denver's defense gave up yards, but forced six takeaways and scored on two of them -- and came within three points of outscoring San Diego's offense.  The second-half play was as good as a pressure, big-play defense gets. Previous game's grade: C-

Special teams: D-

A disastrous first quarter for the return units set up the Chargers for a 24-0 first half that nearly buried the Broncos. It would have been impossible for the recently acquired Trindon Holliday to make a worse first impression than when he fumbled the first time he touched the ball as a Bronco, leading to San Diego's game-opening points via a 32-yard Nick Novak field goal. Holliday showed explosion on a subsequent 12-yard return, but even then backed away from the ball, as though he was scared of another fumble. If ball security trumps all other considerations, the Broncos might go back to Jim Leonhard. Omar Bolden's fumble on a first-quarter kickoff led to the Chargers' first touchdown. Britton Colquitt had a solid 41.8-yard net punting average and Matt Prater was perfect on his placekicks, but overall, the Broncos won in spite of their special teams not because of them. Previous game's grade: C

Coaching: B+

The Broncos looked unprepared and flat early in the first half, and some of that does fall at the feet of the coaches. But they didn't coach their returners to lose two fumbles and their wide receivers to stumble over air. The halftime adjustments were letter perfect, particularly on defense, where coordinator Jack Del Rio began mixing his alignments more often to confuse Rivers and San Diego's offensive line, which often didn't know how to react to where Miller and Dumervil lined up and attacked. Previous game's grade: C+

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