Chargers' draft class impacted by injuries to Mike Williams and Forrest Lamp

Injuries limited Chargers wide receiver Mike Williams to 11 catches for 95 yards and no touchdowns in 10 games during his rookie season. Richard Mackson/USA TODAY Sports

COSTA MESA, Calif. -- The Los Angeles Chargers still don’t know what they have in rookie receiver Mike Williams, who limped through an injury-plagued first season in the NFL.

In addition, the team’s second-round draft pick, offensive lineman Forrest Lamp, didn’t play a single snap during the regular season because of a right ACL injury suffered during the first week of training camp.

However, the Chargers did get contributions from midround prospects such as defensive back Desmond King and offensive lineman Dan Feeney to salvage this year's rookie class.

Grade: Average

Best rookie: King, a University of Iowa product who was selected in the fifth round, developed into a playmaking defensive back and starter at slot defender for the Chargers. King finished with four sacks, 76 tackles and one interception, which he returned 90 yards for a touchdown. King’s four sacks tied him with Rodney Harrison (1997 and '98) for the second-most sacks by a defensive back in a single season in team history. Harrison tops the list with six in 2000.

Most improved rookie: With Matt Slauson suffering a season-ending torn biceps injury, third-round pick Feeney stepped up and filled in at left guard, helping to keep Philip Rivers clean as the Chargers gave up a league-low 18 sacks this season. Feeney played a total of 644 snaps in nine starts.

Most disappointing rookie: Williams missed all of offseason work and training camp with a lower-back disc herniation, finally making it back on the field for a Week 6 contest against the Oakland Raiders. The Clemson product finished the season with 11 catches for 95 yards, including two drops. Williams also suffered a knee injury in a Thanksgiving Day game against the Dallas Cowboys that limited his effectiveness toward the end of the season. The bottom line is that injuries never allowed Williams to develop a consistent rhythm in the offense, and this offseason heading into his second year will be especially important for him.

Jury is still out on: Lamp. The second-round pick suffered a right knee injury during the first week of training camp that put him out for the season. He had surgery in August and will remain with the team to perform his rehab in preparation for the Chargers' offseason program this spring. Lamp was slated to compete for the starting right guard job won by Kenny Wiggins and is expected to help improve the depth of the Chargers' interior offensive line once he’s healthy.

Undrafted rookie evaluation: Austin Ekeler had the most impact among the undrafted rookies. The running back out of Western State Colorado emerged as the No. 2 running back behind Melvin Gordon, finishing with 260 rushing yards, 279 receiving yards and five total touchdowns. Ekeler suffered a broken hand that limited his production the final two games, but he developed into one of the best special-teams players on the roster. Undrafted rookie kicker Younghoe Koo was cut after four games due to his up-and-down play. Cornerback Michael Davis and linebacker James Onwualu also developed into core special-teams players.