SAN DIEGO -- Unhappy with his team's effort on the first day of mandatory minicamp, Los Angeles Chargers head coach Anthony Lynn said players need to improve over the next two days of practice.

"We just looked sluggish," Lynn said. "We committed some fouls -- things that get you beat. Things we haven't done all offseason."

Lynn went on to say the mistakes are correctable, but he wants to stop the poor play now before one bad practice turns into two. Lynn wouldn't bite when asked what he told players after practice.

"I probably can't say that on camera," Lynn said.

However, quarterback Philip Rivers said he appreciates Lynn holding players accountable.

"One thing we've found out early on from Coach Lynn is that he's matter of fact, to the point," Rivers said. "We have to bounce back this afternoon, have a good walkthrough and have a better day tomorrow."

Forrest Lamp, Dan Feeney work with starters: For the first time during an offseason practice open to reporters, second-round selection Forrest Lamp and third-rounder Dan Feeney worked with the starting offense line. Lamp saw time at right guard in place of Kenny Wiggins and Feeney at center with the first group in place of Spencer Pulley. Lynn said he wanted to get a look at different offensive line rotations up front. "We don't want those guys to be jack of all trades, master of nothing," Lynn said. "But right now, we're just looking at different combinations before we get to training camp."

Melvin Ingram arrives at camp: Fresh off his new deal, edge-rusher Melvin Ingram jumped right in and got some work with the starters during team drills on the first day of minicamp. The Chargers placed the franchise tag on Ingram in February, and he had been working out in Florida until he signed his new deal this week. Ingram appeared to be in good shape. "I feel like nothing is different, you just have to come out and play football," Ingram said about signing his new contract, a four-year, $66 million deal that includes $42 million in guaranteed money. "I just love (DC Gus Bradley's) energy. Just the way he comes out. He'll put a smile on your face because he's coming out with a smile on his face. He just wants to be successful and I think all of us want to do that. When we combine everything together, I think we have a great chance of doing that."

Injury update: CB Jason Verrett (knee), CB Casey Hayward (ankle), S Darrell Stuckey (unknown), WR Mike Williams (back), WR Dontrelle Inman (core muscle surgery), DE Chris Landrum (unknown), DE Chris McCain (ankle) and DL Caraun Reid (knee) did not practice on Tuesday. Lynn said that Williams is just resting his back with the hope that the injury will calm down so he can begin rehab. Williams suffered a minor disk herniation that forced the Clemson product to miss the rest of offseason workouts.