San Diego's first-round pick has failed to live up to the hype. He missed one full game and parts of several others due to injury. Additionally, he has lost three fumbles and has yet to run for more than 80 yards in a game. He has shown some big-play ability (he averages a healthy 4.4 ypc and 6.1 yards per reception), but he must put it all together on a consistent basis over the second half of the season.
WR Vincent Jackson
All offseason, the focus was on why Jackson wasn't in San Diego: bad decisions, off-the-field transgressions, etc. Lost in all that mudslinging was the fact he is one of the most dominant offensive players in the game. He will take the top off opposing defenses; create mismatches all over the field, especially in the red zone; and offer excellent run blocking on the outside. It's difficult to imagine Philip Rivers playing at a much higher level, but Jackson's return may help the offense come as close to its full potential as it has ever been.
San Diego's defense has played well in the first nine games, but the defensive line has been pushed around at times. With Luis Castillo now resigned to mediocrity, Martin is lone player with the potential to fully capitalize on the havoc Antonio Garay is wreaking on the inside. The second-year lineman escaped the inactive list in Week 7 and has not looked back. As he gets more comfortable, his athleticism will allow him to win one-on-one matchups and make more plays in the backfield.
LB Larry English
English returned last week in a reserve role after missing six games with a foot injury. With an extra week to rest, he should come back as close to healthy as he is going to get this year. English has two key tasks in the final seven games: 1) provide a consistent pass rush opposite Shaun Phillips, who ranks No. 7 in the league with seven sacks; and 2) help the special teams, especially a punting unit that has become the laughing stock of the NFL.
SS Steve Gregory
Gregory was off to a strong start before a four-game suspension halted his best campaign to date. He returned in Week 9 only to have his comeback end early thanks to a shoulder injury. If he can return to form, it will allow Paul Oliver to slide back into his more familiar role as the dime back. Also, as was the case with English, Gregory's return should spark the special teams, which can use all the help they can get.
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Michael Lombardo is a member of the Pro Football Writers of America and a long-time contributor to the Scout.com network. His analysis has been published by the NFL Network, Fox Sports and MySpace Sports. He has followed the Chargers for more than 15 years and covered the team since 2003. You can see more of his updates by following him on twitter.