Tomlinson looked good in limited work against the Pittsburgh Steelers in Week 4, cutting and accelerating without hesitation. He'll look to keep that going this week versus the Denver Broncos. The last time LT faced Denver, he carried 14 times for 96 yards (6.9 ypc) and three TDs.
2. LT Marcus McNeill: It's no secret San Diego's offensive line must play better over the second half of the season. While any of the team's five linemen could appear on this list, McNeill is the one with the most to prove. He's already allowed three sacks this season, the same number he allowed in all of 2008, and has not provided a steady push as a run blocker on the left side.
McNeill, who is in the final year of his contract, has a lot to prove if he hopes to receive an extension in line with the NFL's top offensive tackles. It starts this Sunday when he matches up against OLB Elvis Dumervil, who leads the NFL with eight sacks.
NT Ogemdi Nwagbuo
In fairness to Nwagbuo, he is not prepared for the starting spot he's been forced to fill. However, he has the quickness and speed in pursuit to make in impact, especially of Ron Rivera can limit him to 25-30 snaps per game to keep him fresh. It's impossible to hide Nwagbuo's inexperience, but if the Bolts' defense is to be effective, it's vital he have a steep learning curve.
4. SS Kevin Ellison: With Clinton Hart no longer in the mix, Ellison is the one who must step up and give the Chargers consistent play at strong safety for the first time since Rodney Harrison was released. True, Steve Gregory may see more playing time than Ellison over the next few weeks, but Gregory doesn't have Ellison's size, power or athleticism.
Ellison will see his minutes expand progressively over the coming games and it's pivotal he take advantage of the opportunity. If he can fulfill his potential this season, the Chargers defense will take an immediate step forward. If not, youngsters Paul Oliver and C.J. Spillman are chomping at the bit.
5. CB Antonio Cromartie: Rarely is a team's most talented player also its worst, but that may very well be the case with Cromartie. Not only has he stopped making big plays -- he's gone more than 12 months since his last interception -- but he's giving up big plays at an alarming rate. The fact that he's among the worst tacklers in the league doesn't help matters either.
The good news for San Diego is that Cromartie is healthy and less than two seasons removed from a 10-interception season, so he clearly has the ability to succeed. The bad news is he's shown no signs of improvement and, with only three corners on the roster, Ron Rivera has nowhere to hide his biggest liability.
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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.