http://www.indystar.com/apps/pbcs.dll/article?AID=/20051213/SPORTS03/512130403 By Mike Chappell LT runs against the ColtsSunday’s Chargers-Colts game in the RCA Dome didn’t require added juice to boost its entertainment value. In what was expected to be a tuneup for their high-octane showdown with the Colts, the Chargers were stunned at home 23-21 by the Dolphins on Sunday. As a result, they find themselves in a four-team chase for the two AFC wild-card playoff spots. Jacksonville, which fell to the Colts 26-18 on Sunday, has the inside track with a 9-4 record and a cushy closing schedule. A step back at 8-5 are the Chargers, AFC West rival Kansas City and Pittsburgh. The Chargers can’t afford another misstep. Never mind seeking revenge for last year’s 34-31 overtime loss in the RCA Dome; San Diego is fighting for survival. Here are some story lines leading up to Sunday’s game: Two of the best: This is as good as it gets for fans of running backs. The Colts feature Edgerrin James, who ranks second in the NFL in total yards from scrimmage (1,743, six behind the Giants’ Tiki Barber) and rushing (1,440, 56 behind Seattle’s Shaun Alexander). The Chargers counter with LaDainian Tomlinson, third in total yards (1,586) and fifth in rushing (1,247). Each is advised to bring his “A” game. The Chargers’ run defense is ranked No. 1, the Colts’ No. 7. Cool Brees: The Chargers are led by former Purdue quarterback Drew Brees, but for how much longer? He was named to his first Pro Bowl in 2004 and set a club record with a 104.8 rating, but he’s playing under a one-year contract as the team’s “franchise” player. Management likely faces a tough decision in the offseason. Does it commit long term to Brees, or allow him to depart via free agency and turn to 2004 first-round draft pick Philip Rivers? Close . . . or not: Something’s gotta give. The Colts have won all 13 games by at least seven points, and nine by double digits. The Chargers’ five losses have been by a combined 14 points. More history?: The Chargers were the opponent last season when Peyton Manning completed his 49th touchdown pass, breaking Dan Marino’s NFL record. Now, they can assist the Colts in joining the ‘72 Dolphins as the only teams in NFL history to post a 14-0 regular-season record.The Miami Dolphins provided some anyway.