Bolts All Under-25 team: Marcus Gilchrist

In this series we take a look at 12 players for the San Diego Chargers who are 25 or younger and who could be considered foundational or impact players.

Player: S Marcus Gilchrist

Age: 25

The skinny: Selected in the second round of the 2011 draft by the Chargers out of Clemson, Gilchrist emerged as a full-time starter in 2013 at safety, playing in the defensive backfield next to Eric Weddle. Gilchrist was drafted as a cornerback, but switched primarily to safety last season. He started 16 games in 2013, playing 951 snaps and finishing third on the team in tackles with 77. Gilchrist also finished the regular season with two interceptions, a sack, a forced fumble, a fumble recovery and five pass breakups.

Reason for optimism: Gilchrist was part of a San Diego secondary playing together for the first time in 2013. Even though the Chargers struggled in the back end at times last season, having that group together again should improve the group's cohesiveness and chemistry, and ultimately the unit's play speed. Gilchrist moved to his familiar spot of nickel cornerback at the end of the regular season and the playoffs, and the Chargers improved as a pass defense. With Johnny Patrick waived and now with the New York Jets, Gilchrist could remain San Diego's nickel cornerback in passing situations.

Reason for concern: Even though he played all 16 games, Gilchrist did suffer some nagging injuries throughout the year. At 5-foot-10 and 198 pounds, he has a slight frame for a safety, and will have to do a good job of building strength this offseason in order to better handle the rigors of an NFL season. Gilchrist also will receive competition for the starting safety job from second-year pro Jahleel Addae.