CHARGER NOTEBOOK : Patten, Friesz on Injured Reserve

The Chargers brought back defensive end Gerald Robinson, who had been cut a day earlier, and claimed cornerback Anthony Shelton off waivers from the 49ers Tuesday. To make room on the roster, the Chargers put tackle Joel Patten and backup quarterback John Friesz on injured reserve.

Patten has not practiced since undergoing knee surgery in late May, and Charger trainers decided he wouldn’t be completely healthy before the third week of the regular season. Players on injured reserve aren’t eligible until after the fourth game.

Friesz, Henning said, injured his shoulder early in training camp and was hurt again in Saturday’s 34-7 loss to the Raiders. That leaves the Chargers with two quarterbacks and punter John Kidd, a backup quarterback at Northwestern.

Shelton will be worked in immediately on special teams and provides the Chargers with depth in a defensive backfield that was exploited by the Raiders.

A rookie from Tennessee State, Shelton was drafted by the 49ers in the 11th round. His athletic ability and speed caught the Chargers’ eye during their exhibition on Aug. 25.

“We think he will be an upgrade for us in the secondary,” Charger Coach Dan Henning said. “Right now, barring injuries, it will be a long time before he gets into the game as a defensive back. But in the meantime, he’ll be able to help us on special teams.”

Guard Dennis McKnight, a nine-year veteran waived Monday by the Chargers, left for Detroit Tuesday after being claimed by the Lions.

McKnight, a Pro Bowl alternate in 1988, missed all of last season with a quadriceps injury. Jerry Wampfler, Detroit’s offensive line coach, was a Charger assistant coach in 1988.

Henning said there is a chance tight end Arthur Cox will be ready to play in Sunday’s regular-season opener at Dallas. Cox, who missed 24 days of practice with a back strain, practiced for the first time Monday in a non-contact workout, and Henning said he is making progress.

Rookie offensive lineman Leo Goeas, who also practiced for the first time Monday since breaking his foot in July, may remain active for the regular season. Goeas, Henning said, is a player with tremendous potential but may take time to develop since he hasn’t yet participated in contact drills.

Until Goeas develops, Eric Floyd will start at left tackle. Floyd spent 13 games on the Chargers’ developmental squad last season.

Henning said linebacker Junior Seau, whose contract holdout cause him to miss most of training camp, has a 60 chance of starting Sunday.

“I certainly feel like he’ll get a lot of playing time,” Henning said. “Based on the way that we played on defense last week, we need all the help that we can get.”