Martin has emerged as the team's go-to receiver during the second half of preseason games. He has hauled in six catches for 83 yards in the first two preseason games, showing the ability to create separation and find soft spots in the defense. He's still a long-shot to make the final roster, but he appears to be a lock for the practice squad.
Martin's wide receivers coach at West Texas A&M, Joel Hinton, has compared Martin to former Denver Broncos standout Ed McCaffrey.
2. DL Ogemdi Nwagbuo -- There doesn't appear to be a winnable spot on the defensive line, but Nwagbuo (6-foot-4, 303 pounds) is certainly giving the team a lot to think about. He plays with a unique combination of quickness and leverage, which allows him to contribute at every spot along the line.
Nwagbuo's ability to play nose tackle is particularly valuable, since the Chargers do not have a pure backup to 33-year-old starter Jamal Williams. Nwagbuo won't command double- and triple-teams like Williams, but he is a disruptive force who can disengage and make tackles at the point of attack.
DL Ogemdi Nwagbuo
Bakhtiari plays to the whistle and constantly strives to improve his game. He's unlikely to make the final 53-man roster due to the team's incredible depth at linebacker, but he seems to be a shoe-in to use his final year of practice-squad eligibility.
4. CB Simeon Castille -- As was first mentioned in last week's Behind Enemy Lines, Castille has put together a strong offseason. Monday's release of CB Cletis Gordon seems to indicate the Chargers agree, as Castille now has a real shot to make the final roster.
Castille, an Alabama product who spent last season with the Cincinnati Bengals, is experienced covering receivers out of the slot and therefore an ideal defender for nickel and dime packages. The Chargers have had their eyes on Castille for a while now, as the team brought him in for a visit prior to the 2008 NFL Draft.
5. FS C.J. Spillman -- Other than Darry Beckwith, Spillman was the biggest name in this year's crop of undrafted free agents. He is a complete safety who is smooth in coverage and reliable against the run. He flashed his potential with a couple big hits against the Arizona Cardinals on Saturday, including one that drew a highly suspect unnecessary-roughness penalty.
Like most of the players on this list, Spillman is fighting for a place in a crowded rotation. Nonetheless, his work on special teams and his knack for making big plays give him a chance to beat the odds.
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.