Chargers' schedule breakdown: Bills

With the San Diego Chargers scheduled to begin training camp on July 24, we take a closer look at the team's opponents for the 2014 regular season.

Third up: Buffalo Bills

When: The Chargers travel to the East Coast for their first 10 a.m. PT start on Sept. 21 at Ralph Wilson Stadium.

Last season: The Bills continued the franchise's streak of missing the playoffs to 14 seasons after finishing 2013 with a 6-10 record. They have the longest active postseason drought in the NFL.

All-time series versus Chargers: San Diego owns a 22-12-2 record all-time over the Bills. The Chargers hold an 8-6-1 record on the road at Buffalo, but have lost three of their last four at Ralph Wilson Stadium.

Last meeting versus Chargers: San Diego defeated Buffalo 37-10 at Qualcomm Stadium on Dec. 11, 2011.

Super Bowl odds: 75-1

Key offseason additions: The Bills were not major players in free agency, but they added some solid complementary pieces in middle linebacker Brandon Spikes (Patriots), running back Anthony Dixon (49ers), cornerback Corey Graham (Ravens) and offensive lineman Chris Williams (Rams). But the players likely to make the most impact were selected in the draft. The Bills got who could be the most explosive playmaker in this year's draft in Clemson receiver Sammy Watkins. Offensive tackle Cyrus Kouandjio and middle linebacker Preston Brown also have a chance to contribute as rookies.

Key offseason losses: Buffalo's defense took two major hits, one in free agency and the other due to injury. The Bills lost their best player in the secondary when Jairus Byrd signed with the New Orleans Saints. Aaron Williams will move from cornerback to man the free safety position for the Bills. Buffalo also lost one of the top playmaking linebackers in the league, after Kiko Alonso tore the anterior cruciate ligament in his left knee while working out at his former stomping grounds, the University of Oregon. With Jim Schwartz taking over as Buffalo's defensive coordinator, Alonso was slated to move to weak side at outside linebacker, with Spikes taking over as middle linebacker in the 4-3 defense. Now the Bills will look for a replacement for Alonso from someone already on the roster, perhaps Nigel Bradham or Brown.

The skinny: Buffalo has one of the more imposing defensive fronts in the NFL. The Bills set a franchise record with 57 sacks last season. Defensive tackle Kyle Williams finished with a career-high 10.5 sacks in 2013. Marcell Dareus earned a Pro Bowl invitation with 71 tackles and 7.5 sacks, and Mario Williams finally played up to his potential, finishing with 38 tackles and 13 sacks. San Diego's offensive line will have its hands full protecting Philip Rivers.

The key for the Bills will be how much quarterback E.J. Manuel improves as a passer in his second season. The Bills ran a league-high 546 times last season. Manuel completed just 58.8 percent of his passes in 2013, throwing 11 touchdowns and nine interceptions. Buffalo needs to get more production from the passing game in order to score points in the red zone and keep opposing defenses from stacking the box to bottle up C.J. Spiller and Fred Jackson.