Watching Philip Rivers this week at Charger Park, reporters saw and heard a familiar performance.

The quick release. The play calls hollered with confidence. The words of encouragment, tinged in an Alabama accent, offered to teammates.

Between the ear holes, however, the quarterback was whirring through a “completely different” code and plan from that which he's most familiar, said Mike McCoy after the coach's first full-squad practice.

“What he’s doing out there is rare,” McCoy said. “He’s picked it up so fast.”

The rookie head coach seems to be placing a big bet on Rivers, the starter since 2006, being able to reduce a large chunk of the learning curve confronting the whole offense.

“We’re going to throw as much of the offense as Philip can handle,” McCoy said. “When he tells us to slow down, we’ll slow down.”

Rivers isn't looking to pump the brakes.

“I’m getting more and more comfortable,” he said.

Hardwired into the quarterback’s brain from the previous system, however, are certain code words whose football definitions, Rivers said, differ “totally” from what they now mean.

When his mind reverts, Rivers hesitates.

“But it doesn’t happen very often,” he said. Smiling, he also said, "I'm glad we're not playing this week."

Rivers said the McCoy-designed practice stood out in one regard: more intermediate passes than typical in recent years.