The San Diego Chargers' return to practice Sunday was a little a shaky. More than 100 small (1.5) to moderate (5.4) earthquakes rumbled through Brawley, Calif., about 130 miles east of San Diego. A few of the larger quakes rattled Chargers Park, but didn't affect practice.  

Ingram update: OLB Melvin Ingram worked out on the side after suffering a deep left thigh bruise against the Vikings on Friday. Ingram may play against the 49ers on Thursday, according to coach Norv Turner. That assessment is optimistic because Ingram appeared to be sore as he walked. Ingram will likely skip Thursday’s final preseason game, but he should be ready to play in the season opener against the Raiders.

Turner impressed with O-line: The OL allowed six sacks against the Vikings. “It may sound crazy,” Turner said. “I was really impressed with the physical style our offensive lineman played. We didn’t play very well together. We have a lot of guys that we have to get on the same page.”

The OL was missing three starters who were replaced by: LT Mike Harris (undrafted, UCLA), LG Rex Hadnot (free agent, Cardinals) and C David Molk (round seven, No. 226 overall). “I didn’t think they were physical break downs,” Turner said of their poor performance. “They need to play together. Some of those guys, I am not sure they know each other’s first name.”

Turner is hopeful starting C Nick Hardwick (concussion), LG Tyronne Green (foot) and LT Jared Gaither (back spasms) will be able to play in Week 1. Green returned to full practice Sunday, Hardwick wore sunglasses and observed and Gaither worked out on the side.

Defense improved: The defense had four takeaways (three fumbles and an INT) against the Vikings. San Diego was second to last with four recovered fumbles in 2011.

“We have improved our team speed and athleticism,” Turner said. “We are playing very quickly. When you put those things together, we are getting to the ball. I think [forced turnovers] is going to be an identity of our defensive team.”

Kaeding happy with performance: Nate Kaeding kicked his first two field goals (50 and 54 yards) on Friday since he tore an ACL in last season’s opening play, which was also against the Vikings. “It was good to get out in a practice game and hit a few,” Kaeding said. “It certainly wasn’t a surprise when I went out there and kicked it. It’s been a good month of preparation.”

Injury updates: DE-DT Garrett Brown (left foot), RB Curtis Brinkley (strain), LT Jared Gaither (back spasms), DT Antonio Garay (left foot), CB Marcus Gilchrist (hamstring), OLB Melvin Ingram (thigh), RB Ryan Mathews (clavicle), TE Dante Rosario (unknown), G Johnnie Troutman (pectoral) and ILB Demorrio Williams (unknown) worked out on the side and did not practice. Also not practicing: WR Vincent Brown (ankle), G-T Brandyn Dombrowski (foot, cyst), C Nick Hardwick (concussion), S Darrell Stuckey (unknown). Stuckey, who didn't play Friday, went to the training room during stretching. Ingram and Stuckey were new additions to the nonparticipants list. CB Shareece Wright (hamstring) returned to full participation.

What’s next: The Chargers will cut their roster from 88 to 75 players by 1 p.m. Monday. There will then be a full practice at 1:30 pm. All practices are now closed to public.

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