As he has grown into a comfort level with the offense, he has also been biting his nails and gnawing footballs at the chance to start and show his wares.
The two-year apprenticeship is over. This is the Rivers show now.
It was, therefore, understandable that the third-year quarterback from North Carolina State was eager to hit the field in the first veteran/rookie session.
"I've been kind of eager for this day to get here, just to get back out on the field," Rivers admitted.
"He looked very comfortable out there," head coach Marty Schottenheimer acknowledged. "He threw the ball with confidence."
But he has a lot to learn.
The Chargers are banking on Rivers to be the guy this year – and that doesn't just include taking the snap from center.
There are expectations for this team. It begins and ends with the postseason. The team allowed Brees to test free agency – the quarterback who led them to 20 victories over the last two years. Rivers helped lead the team to one – and he was the backup to the now retired Doug Flutie in that game.
With a team that was deemed talented enough to vie for a playoff spot last season, San Diego has entrusted Rivers with leading them back for the second time in three years.
But Brees had a lot of believers on this team and Rivers has to win over the veterans.
"I still feel like I have some respect and trust to earn these next couple of months," Rivers added. "It's time for me to step up and take control."
From the first time he entered the huddle, Rivers has demanded respect. His demeanor is one of cool confidence and the team will surely back him now. After all, the team is going through coaching sessions and not real game action. They will bleed for him now.
Offensive coordinator Cam Cameron said it best during an interview with reporters in Houston:
"Our quarterback has to understand it's about the team," he said. "It's about leading our team and putting our team in a position to be successful. It's not about the individual."
But should he be inconsistent when the season begins, Rivers may have a tough time lifting his head to look in the eyes of his teammates.
"We have a lot of leaders on this team," Rivers said. "There are a lot of veteran players that know how to win and how to lead. They're going to help carry the load, but because of my position I have some unique responsibilities. I'm ready to take control and do everything I can to lead this team."
Leading is directly tied to wins in this case.