Chargers at Broncos -- Week 11 

Where: Sports Authority Field, Denver (grass, outside)

When: Sunday, 4:15 p.m. ET (CBS)

Spread: Broncos by 6.5

Forecast: Partly cloudy with temperatures in the high 50s.

Records: Chargers (4-5, 3-1 AFC West); Broncos (6-3, 2-0 AFC West)

Past results: Two most recent meetings -- Oct. 15, 2012, Broncos 35, Chargers 24; Oct. 9, 2011, Chargers 29, Broncos 24. The Chargers have won four out of the last six meetings. Series Record: Denver leads the all-time series 56-48-1.

What matters: The battle for the AFC West will swing by three games. If the Chargers win, they will trail the Broncos by just one game. If the Broncos win, they will have a three-game lead with six to play. Denver would also own the first tie-breaker, head-to-head record; therefore the Broncos actual lead would be four games.

Who matters: Chargers QB Philip Rivers needs to play a nearly flawless game. He has thrown 12 interceptions this season and is on pace to throw 21, one more than last season’s career-high of 20. Rivers is in the middle of a streak where he throws at least one horrible pass per game directly into coverage. Last week, that pass was picked off by Buccaneers CB Leonard Johnson and returned 83 yards for a game-changing TD. In Week 6, Rivers turned the ball over six times, including five times in the second half on three interceptions and two fumbles. The turnovers allowed the Broncos to erase a 24-0 halftime deficit and complete an historic Monday Night Football comeback to win 35-24.

Broncos QB Peyton Manning caught fire in the second half of Week 6 and has remained hot. In his three games since, he has completed 76 of 103 passes for 897 yards and seven TDs with only two INTs. That gives him a three-game passer rating of 114.4. For the season, Manning has thrown for 2,705 yards and 21 TDs with only six INTs. He leads the league with a 108 passer rating of all qualified quarterbacks.

RB Ryan Mathews hasn't rushed for over 100 yards this season. Three of his five career 100-plus-yard performances have come in the five previous times he has faced Denver. Mathews (stiff neck) missed practice on Wednesday and Thursday and is listed as questionable. He likely will play, but his ability to contribute may be limited. If Mathews can rush for more than 100 yards, it would help keep the pressure off of Rivers and allow the Chargers to control the ball, which would limit Manning.

Key matchups: Chargers LT Mike Harris (undrafted, UCLA) vs. Broncos RDE Elvis Dumervil or Robert Ayers. Starting LT Jared Gaither (groin) did not practice this week and is listed as doubtful. The Broncos lead the league with 31 sacks. Dumervil has seven sacks with five forced fumbles, including two sacks and two forced fumbles of Rivers in Week 6. Dumervil leads all Broncos defenders with eight career sacks against the Chargers. San Diego may catch a break, however, because Dumervil (shoulder) is listed as questionable. Ayers, a first-round pick in 2009, would play in place of Dumervil. Ayers had the best performance of his career last week with three tackles (two solo and one assist), one sack and two passes defensed.

Injuries of note: For San Diego: NT Aubrayo Franklin (knee) is out and will be replaced by Antonio Garay, who started 28 games for the Chargers from 2010-11. Backup TE Dante Rosario (hamstring) is also listed as questionable. For Denver: CB Tracy Porter (seizure related symptoms) will miss his fifth straight game.  RG Chris Kuper (ankle) has been limited all week and is doubtful.

Inside stuff: Special teams could play a big factor. Broncos PR-KR Trindon Holliday has had two returns for touchdowns in the last two weeks. The Chargers special teams recovered two fumbles on kicks against Denver in Week 6. “We know as a special teams unit that we are the biggest difference in the game,” said S Darrell Stuckey, the Chargers special teams captain. “Any time you can cause a turnover, it’s big.”

Connections: WR Eddie Royal was a second-round pick of the Broncos in 2008 and was with the club through last season. Rosario played for the Broncos in 2011. Broncos coach John Fox served as the Chargers secondary coach from 1992-93.

Record watch: TE Antonio Gates (80) needs one touchdown catch to match WR Lance Alworth (81) for the franchise record. OLB Shaun Phillips has 65.0 career sacks, fourth in team history. Phillips needs one half sack to tie Lee Williams (65.5) for third, and he needs two sacks to tie Gary “Big Hands” Johnson (67) for second.

Stat you should know: Rivers has completed 109 of 165 passes (66.1 percent) for 1,577 yards with nine TDs and five INTs in six career starts at Sports Authority Field. He's 9-4 as a starter against Denver. The Chargers are 4-2 against Manning under coach Norv Turner, which includes two playoff wins. The Chargers have won the last three and five of their last six in Denver.

Looking ahead: In Week 12, The Chargers' schedule doesn't get any easier. San Diego will host the AFC North leading Ravens (7-2).  The Broncos travel to take on the woeful Chiefs (1-8).

Prediction: Chargers 27, Broncos 24

Follow the Chargers and Dan McLellan on Twitter @CBSChargers and @sandiegosports.