San Diego (5-1) leads the AFC West by a half-game over Oakland (4-1) and has already matched their win total of last year, when the Chargers went 5-11. Parrella spent eight seasons in a Charger uniform before signing with the Raiders as a free agent. Shaw, who was a teammate of Parrella, spent five seasons in San Diego before going to Miami and New England for one year each. Shaw, like Parrella, is in his first season as a Raider.
"Most of the guys on offense have changed," Parrella said. "I played there for a long time, but now I'm here and this is an important game for us. They've obviously improved. It's going to be a battle. I always remember coming up here and how tough it was."
The Chargers chose not to resign Parrella. Oakland, meanwhile, wasted little time inking Parrella, who declined to discuss his departure from San Diego.
"I loved my time there but that's over," Parrella said. "One of the reasons I chose to come here was because of the defensive line coach (Mike Waufle) and to be surrounded by a lot of good players."
Linebacker Junior Seau and safety Rodney Harrison are two Charger defenders that received more notoriety than Parrella. Oakland offensive players, however, are fully aware of Parrella's impact – then and now.
"I went back and looked at my notes from a year ago," Raiders quarterback Rich Gannon said. "Three or four times there's notes about Parrella. He jumps and bats balls; he's a looping guy in the stunt game. All these different notes we had a year ago in our book about playing these guys, and fortunately for us, he's on our team this year. He was a big part of their success not only stopping the run, but a real penetrator and a real force against the pass as well. That was a big acquisition for us."
Shaw, meanwhile, is not as diplomatic as Parrella about his former team despite earning a Super Bowl ring while playing for New England last season. The Chargers released by the Chargers after the 1999 campaign before going to Miami. Shaw, who is Oakland's nickel corner, referred to Sunday's game as "personal" and did not hide the fact that he holds a grudge.
"I had knee surgery and they tried to say, 'He's not a player,'" Shaw said. "Every time I wake up and my knee hurts, I think of San Diego."