Denis Poroy/Associated Press

Being a Chargers fan in 2016 must have felt like getting a 200-foot head start in a race every week and still eating dirt at the end. Then a few extra shovels of dirt were tossed on when your team packed up, moving from San Diego to Los Angeles.

The Chargers lost 11 games and dropped eight of them by seven points or fewer. The most maddening stretch came early between Weeks 3 and 5 when they lost three straight by a combined eight points.

After plenty of time to digest that frustrating season, there's an easy way to start believing in the Chargers again. They were competitive, and now they've secured the needed defensive pieces.

The final step was making sure outside linebacker Melvin Ingram wouldn't go anywhere. He had been franchise-tagged, but that only meant he'd be on the Chargers roster for one more year.

When the Chargers announced a four-year contract Sunday afternoon, they retained one of the league's fastest-rising young pass-rushers and laid down arguably the final building block.

Ian Rapoport of NFL Network broke down the details:

The total amount of guaranteed money might seem steep, but Ingram can easily justify the Chargers' decision to fill his backyard pool with gold coins. He's already been doing that the past two seasons.

The $42 million in guaranteed money ranks fourth among all outside linebackers, according to Spotrac. A 28-year-old who likely has at least four prime years left—also known as the length of his new contract—has shown he's worth every cent when healthy.

Ingram struggled with injuries earlier in his career, missing 19 games over the 2013 and 2014 seasons. But those issues have been corrected now over a two-year run when he hasn't busted, ripped or bruised anything while playing 32 straight games.

Prior to that stretch, the former first-round pick had teased with his talent and burst off the edge. The image of a healthy Ingram was there in your imagination, but it was foggy.

Then after a career-high 10.5 sacks in 2015, Ingram went ahead and confirmed that, yes, he's everything you imagined. As Pro Football Focus noted, only three other players at his position registered more pressures in 2016:

That's why his sack total is deceiving and doesn't tell the true story. He finished 2016 with eight sacks, which sounds solid though not spectacular. But the best pass-rushers are able to consistently penetrate into the backfield and disrupt plays even when they don't reach the quarterback.

In that sense, the league's top tier of quarterback chasers are a constant looming presence offensive coordinators need to game-plan around. They can alter the usual structure of an offense by forcing more shotgun and max-protect formations, and they can minimize the number of quality downfield pass attempts by making the quarterback's internal clock tick faster.

So what happens when the Chargers field two such pass-rushers over a full season for the first time in 2017? We're about to find out after defensive end Joey Bosa, the other half of the league's menacing young pass-rushing duo, was named the Defensive Rookie of the Year in 2016.

What Bosa did as a rookie usually requires Madden cheat codes. He missed four games after the Chargers were senselessly stubborn in their rookie contract negotiations, resulting in a stalemate that didn't end until late August. Bosa then suffered a hamstring injury while rushing as he tried to get prepared for game action.

He still finished with 10.5 sacks. Over four fewer games, for reference, that was only a half-sack behind the Raiders' Khalil Mack.

Bosa especially sizzled over the Chargers' final six games of 2016, a period when he recorded at least a half-sack each week. In total between Weeks 12 and 17, Bosa logged 6.5 sacks. He was historically dominant, and his 60 pressures were the most by any pass-rusher since 2006 during his first 12 games, per PFF.

So the Chargers have one pass-rusher who's already established himself as a game-changing force. And Ingram, an edge-rusher who was among the league leaders in pressures even during a season when the Chargers asked him to drop back 106 times in coverage.

Ingram and Bosa are the two core pieces who can take a sizable bite out of the 26.4 points per game the Chargers defense allowed in 2016 (29th). But the intrigue doesn't end there.

Cornerback Casey Hayward, 27, reverted to the 2012 version of himself after joining the Chargers, recording 25 passes defensed (second) and leading the league with seven interceptions.

Much like Ingram and Bosa up front, the Chargers also have an elite duo in their defensive backfield. Jason Verrett is healthy now after missing much of 2016 due to a torn ACL. The 25-year-old is only one year removed from a Pro Bowl season, and he allowed just 56 percent of the passes thrown his way to be completed over his first two years in the NFL.

Verrett's returning to play alongside Hayward should put a dent in the 347.1 yards per game the Chargers allowed in his absence (16th). And in front of them is middle linebacker Denzel Perryman, the second-round pick who's had a great start to his career and also shined in 2015:

Led by Bosa and Ingram, the Chargers' young defense can grow together. Merely getting a full season from Bosa and Verrett can vault Los Angeles far up from its lowly 2016 defensive ranking, possibly to top-10 territory.

It's a defense anchored in critical places by two pass-rushers and two quality coverage cornerbacks. Those are key components in an AFC West that's been driven by a defensive arms race.

The division is home to two top-10 defenses by points allowed in 2016: Denver Broncos (fourth), Kansas City Chiefs (seventh). And the Oakland Raiders also have a youth-filled unit led by Mack, along with fast-emerging safety Karl Joseph and cornerback Gareon Conley, their 2017 first-round pick.

The AFC West will be a season-long cage match won by the team able to get to the quarterback. The Chargers can do that in 2017 and beyond.