Justin Herbert and the Los Angeles Chargers are off to a 2-0 start in Jim Harbaugh's first season as the team's head coach. After a win against the Las Vegas Raiders, the Chargers won 26-3 against the Panthers in Week 2.Unfortunately, Herbert suffered an injury during the team's win against the Panthers. Reports indicate that the team has diagnosed the quarterback with an ankle sprain.He did not practice on Wednesday and was limited on Thursday. As of now, the team has not made a decision regarding the quarterback's availability in Week 3.Harbaugh did mention that Herbert is working his way through fitness and could play on Sunday. The Chargers will face the Pittsburgh Steelers in Week 3, who are also off to a 2-0 start.Going against the Steelers' defense is a tough task for any team. It will be extremely tough for the AFC West franchise to win this week if they are without their star quarterback.Justin Herbert injury: Who is Chargers' QB2?NFL: SEP 15 Chargers at Panthers - Source: GettyIf Justin Herbert is ruled out for Sunday's game, then the team will have to rely on Easton Stick. Here's the quarterback depth chart of the Chargers heading into Week 3:Justin Herbert - QB1Easton Stick - QB2Taylor Heinicke - QB3Stick has started four games so far in his career and has lost all of them. In those games, he has thrown for 950 yards, three touchdowns, and one interception with a passer rating of 86.8.The Chargers have heavily relied on the running game this season, and that will continue in Week 3 even if Herbert plays. In two games, they are averaging 197.5 rushing yards per game, with J.K. Dobbins leading from the front.Dobbins has rushed for 266 yards and two touchdowns on 27 carries, averaging an impressive 9.9 yards per carry. Justin Herbert has not been asked to do much this season, and even if he is not 100%, the Chargers could still roll him out on the field.The Chargers quarterback has thrown for 274 yards, three touchdowns, and an interception over the first two games of the season with a passer rating of 95.7.Update on Justin Herbert's status for Week 3: Herbert will be be active for Week 3 vs the Steelers. Reports added that his warmup went well, and the team will have 3 QBs for the day.