In the Super Bowl era, only 5 teams have had the #1 Offense and #1 Defense in the same season (1972 Dolphins, 1973 Rams, 1977 Cowboys, 1987 49ers, 2010 Chargers). Of those 5, 2 won the Super Bowl (1972 Dolphins, 1977 Cowboys), 2 lost in the Division Round (1973 Rams, 1987 49ers), and 1 missed the playoffs completely (2010 Chargers).

That 1 begs the question: How?

The Dominance

For the record, I hate Philip Rivers, he's annoying, and has the ugliest throwing motion ever. But I'll give him some due credit, if Dan Marino is the best Quarterback to never win the Super Bowl, then Philip Rivers is the best Quarterback to never go to the Super Bowl. And his 2010 performance put him in rare company, as 1 of only 4 Quarterbacks to have 3 consecutive seasons with a Passer Rating over 100.
In 2010, Rivers had the most 400+ yard passing games with 2, was #1 in passing yards with 4,710, #1 in passing yards per game with 294.4, and #1 in most yards per pass with 8.7.
In their first season since 2000 without LaDainian Tomlinson (requested his release in the offseason), the Chargers offense was #1 in total offensive yards with 6,329, and #1 in yards per play with 6.1.

The defense was #1 in passing and #4 in rushing for an overall ranking of #1. They were #1 in yards allowed with 4,345, #1 in passing yards allowed with 3,135, #1 in yards allowed per game with 271.6, and #1 in first downs allowed with 247.

They were a team that seemingly had it all figured out. On paper, you could almost be forgiven for thinking they were unstoppable. So, where did all the wins go? Every now and then, a team’s run of bad luck can be explained away by them just having a turnover problem, but not so much with the Chargers. They only had a turnover differential of -6 in 2010, meaning they gave up the ball 6 more times than they took it away. Obviously not good, but not the worst either. The Colts (-4), Saints (-6), and Seahawks (-9) all had negative turnover differentials and managed to make the playoffs. If anything, the Chargers were simply below average on turnovers, so this explanation doesn’t really work for them.

The Problem

It’s no secret that Special Teams was their downfall, but the word-of-mouth history of the 2010 Chargers has gotten a little skewed over the years with that word being, "they had a kick or punt returned on them, like, every game". However, this is blowing their failure a little out of proportion, only 4 kickoffs/punts were actually returned for touchdowns. But this is not to undermine the fact that their Special Teams completely screwed them, because those 4 meant they led the league in return touchdowns allowed.

Week 1 @ Kansas City Chiefs

After a 34-yard punt return marred by bad coverage, and a 22-yard punt return marred by bad tackling, the Chiefs took it to the house on a 94-yard punt return touchdown. The Chargers lost by 7.

Week 3 @ Seattle Seahawks

Seattle returned the second half kickoff for a 101-yard touchdown. Then after the Chargers' stacked offense mounted a comeback to tie the game in the 4th quarter, Seattle returned a second kickoff for a 99-yard touchdown. The Chargers lost by 7.

Week 5 @ Oakland Raiders

In the 2010 season there were 12 blocked punts across the league, 4 of them were on the Chargers... Which, of course, led the league. 2 of them occurred in the same game against the Raiders. The first rolled out of the back of the endzone for a Safety, and the second was a scoop-n-score touchdown, for a total of 9 points. The Chargers lost by 8.

Mind-blowing Fun Fact: In 2010, the Raiders led the league in blocked punts... with 2. Both occurred in the same quarter of the same game on back-to-back possessions, with both resulting in a defensive score. (That's gotta be the only time that's ever happened. Someone with access to more stats than I do can fact check that, but it wouldn't surprise me.)

Week 6 @ St. Louis Rams

A 4th quarter field goal attempt was blocked when kicker Nate Kaeding lost his footing and slipped. The Chargers lost by 3.

Week 7 vs. New England Patriots

With 23 seconds left in the 4th quarter, a 5-yard False Start penalty moved the Chargers back, and a 45-yard field goal attempt became a 50-yard attempt and was no good after hitting the upright. The Chargers lost by 3.

The Legacy

All of these happened not even halfway through the season, as the Chargers got off to a 2-5 start. They would go on to win 7 of their 9 remaining games, but the damage was already done. They missed the playoffs by 1 game behind the Kansas City Chiefs.

Now these could all be considered isolated incidents with no definitive proof that these specific plays caused the Chargers to lose. So, let’s look at some more of their overall season stats.

By the end of the 2010 season, the Chargers led the league in return yards allowed with 2,408 (4th most in NFL history), and average yards per return allowed with 18.4 (also 4th most in NFL history, tied). But here's the kicker (pun intended), punt returns specifically were truly historic. It was the worst season in Punter Mike Scifres career, with a total of 528 punt return yards allowed. The Chargers led the league in average punt return yards allowed with 18.9, which to this day, is an NFL record.